Examples with solutions for Variables and Algebraic Expressions: Applying the formula

Exercise #1

3x+4x+7+2=? 3x+4x+7+2=\text{?}

Video Solution

Step-by-Step Solution

Let's simplify the expression 3x+4x+7+2 3x + 4x + 7 + 2 step-by-step:

  • Step 1: Combine Like Terms Involving x x
    The terms 3x 3x and 4x 4x are like terms because both involve the variable x x . To combine them, add their coefficients:
    3x+4x=(3+4)x=7x 3x + 4x = (3 + 4)x = 7x

  • Step 2: Combine Constant Terms
    The expression includes constant terms 7 7 and 2 2 . These can be added together to simplify:
    7+2=9 7 + 2 = 9

  • Step 3: Write the Simplified Expression
    Now, combine the results from Step 1 and Step 2 to form the final simplified expression:
    7x+9 7x + 9

Therefore, the simplified expression is 7x+9 7x + 9 .

Reviewing the choices provided, the correct choice is:

  • Choice 2: 7x+9 7x + 9

This matches our simplified expression, confirming our solution is correct.

Answer

7x+9 7x+9

Exercise #2

3z+19z4z=? 3z+19z-4z=\text{?}

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Combine like terms by identifying and adding their coefficients.
  • Step 2: Simplify the expression.
  • Step 3: Verify the resulting expression with the provided choices.

Let's work through each step:

Step 1: Identify the coefficients in the expression 3z+19z4z 3z + 19z - 4z . The coefficients are 3 3 , 19 19 , and 4 -4 .

Step 2: Add and subtract these coefficients: 3+194 3 + 19 - 4 .

Step 3: Calculate: 3+19=22 3 + 19 = 22 and then 224=18 22 - 4 = 18 .

Therefore, the simplified expression is 18z 18z .

The solution to the problem is 18z 18z .

Answer

18z 18z

Exercise #3

7a+8b+4a+9b=? 7a+8b+4a+9b=\text{?}

Video Solution

Step-by-Step Solution

To simplify the expression 7a+8b+4a+9b 7a + 8b + 4a + 9b , we will follow these steps:

  • Step 1: Identify like terms. The expression contains terms involving a a (7a 7a and 4a 4a ) and terms involving b b (8b 8b and 9b 9b ).
  • Step 2: Combine the coefficients of like terms.
  • Step 3: Rewrite the simplified expression.

Step 1: The like terms involving a a are 7a 7a and 4a 4a .

Step 2: Add these coefficients: 7+4=11 7 + 4 = 11 . Therefore, the combined term for a a is 11a 11a .

Step 3: The like terms involving b b are 8b 8b and 9b 9b .

Step 4: Add these coefficients: 8+9=17 8 + 9 = 17 . Therefore, the combined term for b b is 17b 17b .

Thus, the expression simplifies to 11a+17b 11a + 17b .

The correct answer choice is: 11a+17b 11a + 17b .

Answer

11a+17b 11a+17b

Exercise #4

18x7+4x98x=? 18x-7+4x-9-8x=\text{?}

Video Solution

Step-by-Step Solution

To solve the exercise, we will reorder the numbers using the substitution property.

18x8x+4x79= 18x-8x+4x-7-9=

To continue, let's remember an important rule:

1. It is impossible to add or subtract numbers with variables.

That is, we cannot subtract 7 from 8X, for example...

We solve according to the order of arithmetic operations, from left to right:

18x8x=10x 18x-8x=10x 10x+4x=14x 10x+4x=14x 79=16 -7-9=-16 Remember, these two numbers cannot be added or subtracted, so the result is:

14x16 14x-16

Answer

14x16 14x-16

Exercise #5

13a+14b+17c4a2b4b=? 13a+14b+17c-4a-2b-4b=\text{?}

Video Solution

Step-by-Step Solution

To solve the problem, we should simplify the expression by combining like terms:

  • Step 1: Identify like terms.
    • The terms involving a a are 13a 13a and 4a-4a.
    • The terms involving b b are 14b 14b , 2b-2b, and 4b-4b.
    • The term involving c c is 17c 17c.
  • Step 2: Combine like terms by summing their coefficients:
    • For a a -terms: 13a4a=(134)a=9a 13a - 4a = (13 - 4)a = 9a.
    • For b b -terms: 14b2b4b=(1424)b=8b 14b - 2b - 4b = (14 - 2 - 4)b = 8b.
    The c c term remains unchanged as 17c 17c .

Therefore, the simplified expression is 9a+8b+17c 9a + 8b + 17c .

Checking the choices provided, we see that the correct answer is 9a+8b+17c 9a + 8b + 17c , which matches choice .

Thus, the final simplified expression is 9a+8b+17c 9a + 8b + 17c .

Answer

9a+8b+17c 9a+8b+17c

Exercise #6

a+b+bc+9a+10b+3c=? a+b+bc+9a+10b+3c=\text{?}

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Identify and group like terms.
  • Step 2: Combine the coefficients for each type of term.

Let's begin the simplification process:

First, we identify and group the like terms in the expression a+b+bc+9a+10b+3c a + b + bc + 9a + 10b + 3c .

Notice: - The terms involving a a are a a and 9a 9a . - The terms involving b b are b b and 10b 10b . - The terms involving c c are 3c 3c , and the multiplication term with c c is bc bc .

Step 2: Combine the like terms:

a+9a=10a a + 9a = 10a

b+10b=11b b + 10b = 11b

The term bc bc can be rearranged with 3c 3c as (b+3)c(b+3)c.

Thus, after combining the terms, we have:

10a+11b+(b+3)c 10a + 11b + (b + 3)c .

Therefore, the simplified form of the expression is:

10a+11b+(b+3)c 10a + 11b + (b + 3)c

Answer

10a+11b+(b+3)c 10a+11b+(b+3)c

Exercise #7

35m+9n48m+52n=? 35m+9n-48m+52n=?

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Identify and group like terms within the expression.
  • Combine the coefficients of these like terms.
  • Simplify the expression by adding or subtracting coefficients.

Now, let's work through each step:

Step 1: Observe the given algebraic expression:
    35m+9n48m+52n35m + 9n - 48m + 52n.

Step 2: Group like terms, separating terms with mm from those with nn:
    (35m48m)(35m - 48m) and (9n+52n)(9n + 52n).

Step 3: Combine the terms with mm:
    35m48m=(3548)m=13m35m - 48m = (35 - 48)m = -13m.

Step 4: Combine the terms with nn:
    9n+52n=(9+52)n=61n9n + 52n = (9 + 52)n = 61n.

Therefore, the simplified form of the expression is:
    61n13m61n - 13m.

This leads to our final solution:

61n13m61n - 13m

Answer

61n13m 61n-13m

Exercise #8

Simplify the following expression:

8y+4534y45z=? 8y+45-34y-45z=\text{?}

Video Solution

Step-by-Step Solution

In order to solve this question, remember that we can perform the addition and subtraction operations when we have the same variable.
However we are limited when we have several different variables.
 

Note that in this exercise that we have three variables:
45 45 which has no variable
8y 8y and 34y 34y which both have the variable y y
and 45z 45z with the variable z z

Therefore, we can only operate with the y variable, since it's the only one that exists in more than one term.

Rearrange the exercise:

4534y+8y45z 45-34y+8y-45z

Combine the relevant terms with y y

4526y45z 45-26y-45z

We observe that this is similar to one of the other answers, with a small rearrangement of the terms:

26y+4545z -26y+45-45z

Given that we have no possibility to perform additional operations - this is the solution!

Answer

26y+4545z -26y+45-45z

Exercise #9

5a+3a+8b+10b=? 5a+3a+8b+10b=\text{?}

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Identify the like terms in the expression.
  • Step 2: Combine these like terms by adding their coefficients.

Now, let's work through each step:

Step 1: In the expression 5a+3a+8b+10b5a + 3a + 8b + 10b, we have two types of like terms:

  • Terms involving aa: 5a5a and 3a3a.
  • Terms involving bb: 8b8b and 10b10b.

Step 2: Combine like terms:

  • For the terms involving aa: Combine 5a+3a5a + 3a to get 8a8a.
  • For the terms involving bb: Combine 8b+10b8b + 10b to get 18b18b.

The simplified expression combining all the terms is 8a+18b8a + 18b.

Therefore, the solution to the problem is 8a+18b 8a + 18b .

Answer

8a+18b 8a+18b

Exercise #10

3.43.4a+2.6b7.5a=? 3.4-3.4a+2.6b-7.5a=\text{?}

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Identify the terms involving the same variables.
  • Combine like terms, particularly those involving a a .
  • Simplify the expression based on the calculations.

Now, let's work through each step:
Step 1: The given expression is 3.43.4a+2.6b7.5a 3.4 - 3.4a + 2.6b - 7.5a .
Step 2: Identify the like terms:
- The terms with a a are 3.4a -3.4a and 7.5a -7.5a .
Step 3: Combine these like terms:
- Calculate 3.4a7.5a=(3.47.5)a=10.9a -3.4a - 7.5a = (-3.4 - 7.5)a = -10.9a .
Step 4: Substitute back into the expression:
- The simplified expression is 3.410.9a+2.6b 3.4 - 10.9a + 2.6b .

Therefore, the solution to the problem is 3.410.9a+2.6b 3.4 - 10.9a + 2.6b .

Answer

3.410.9a+2.6b 3.4-10.9a+2.6b

Exercise #11

7.34a+2.3+8a=? 7.3\cdot4a+2.3+8a=\text{?}

Video Solution

Step-by-Step Solution

It is important to remember that when we have numbers and variables, it is impossible to add or subtract them from each other.

We group the elements:

 

7.3×4a+2.3+8a= 7.3×4a + 2.3 + 8a =

29.2a + 2.3 + 8a = 

37.2a+2.3 37.2a + 2.3

 

And in this exercise, this is the solution!

You can continue looking for the value of a.

But in this case, there is no need.

Answer

37.2a+2.3 37.2a+2.3

Exercise #12

7.8+3.5a80b7.8b+3.9a=? 7.8+3.5a-80b-7.8b+3.9a=\text{?}

Video Solution

Step-by-Step Solution

To solve this problem, we need to simplify the given expression:

1. Identify and group similar terms:

  • Constant term: 7.8 7.8
  • Terms with a a : 3.5a+3.9a 3.5a + 3.9a
  • Terms with b b : 80b7.8b-80b - 7.8b

2. Simplify each group:

  • Combine terms with a a :
    3.5a+3.9a=(3.5+3.9)a=7.4a 3.5a + 3.9a = (3.5 + 3.9)a = 7.4a
  • Combine terms with b b :
    80b7.8b=(807.8)b=87.8b -80b - 7.8b = (-80 - 7.8)b = -87.8b

3. The constant term remains 7.8 7.8 .

4. Therefore, the simplified expression is:
7.8+7.4a87.8b 7.8 + 7.4a - 87.8b

Thus, the correct answer is 7.8+7.4a87.8b\boxed{7.8 + 7.4a - 87.8b}

Answer

7.8+7.4a87.8b 7.8+7.4a-87.8b

Exercise #13

39.3:4a+5a+8.2+13z=? 39.3:4a+5a+8.2+13z=\text{?}

Video Solution

Step-by-Step Solution

To solve the problem, we will simplify the expression 39.3:4a+5a+8.2+13z 39.3 : 4a + 5a + 8.2 + 13z . Let's break down the steps:

  • Step 1: Simplify the division 39.3:4a 39.3 : 4a .
    To solve 39.3:4a 39.3 : 4a , we treat this as 39.34a \frac{39.3}{4a} .
    Calculating the division: 39.34=9.825 \frac{39.3}{4} = 9.825 . Therefore, 39.34a=9.825a \frac{39.3}{4a} = \frac{9.825}{a} .
  • Step 2: Rearrange the terms.
    We now have 9.825a+5a+8.2+13z \frac{9.825}{a} + 5a + 8.2 + 13z . No like terms for direct combination exist as these are distinct variables and constants.
  • Step 3: Write the expression.
    The terms should be written in a neat, arranged form as 13z+8.2+9.825a+5a 13z + 8.2 + \frac{9.825}{a} + 5a .

Therefore, the simplified expression is  13z+8.2+9.825a+5a\ 13z + 8.2 + \frac{9.825}{a} + 5a .

Answer

13z+8.2+9.825a+5a 13z+8.2+\frac{9.825}{a}+5a

Exercise #14

5.6x+7.9y+53xy+12.1x=? 5.6x+7.9y+53xy+12.1x=\text{?}

Video Solution

Step-by-Step Solution

To solve this problem, follow these steps:

  • Step 1: Identify Like Terms
  • The expression is 5.6x+7.9y+53xy+12.1x 5.6x + 7.9y + 53xy + 12.1x . Here, 5.6x 5.6x and 12.1x 12.1x are like terms.

  • Step 2: Combine Like Terms
  • Add the coefficients of x x : 5.6x+12.1x=(5.6+12.1)x=17.7x 5.6x + 12.1x = (5.6 + 12.1)x = 17.7x .

  • Step 3: Write the Simplified Expression
  • After combining the like terms, we get:

    17.7x+7.9y+53xy 17.7x + 7.9y + 53xy

    This is the simplified form of the expression.

    Therefore, the solution to the problem is 17.7x+53xy+7.9y 17.7x + 53xy + 7.9y .

Answer

17.7x+53xy+7.9y 17.7x+53xy+7.9y

Exercise #15

14a+13x+24a+18+38=? \frac{1}{4}a+\frac{1}{3}x+\frac{2}{4}a+\frac{1}{8}+\frac{3}{8}=\text{?}

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Combine like terms.
  • Step 2: Simplify the expression.

Now, let's work through each step:
Step 1: Start by identifying and combining like terms in the expression 14a+13x+24a+18+38\frac{1}{4}a + \frac{1}{3}x + \frac{2}{4}a + \frac{1}{8} + \frac{3}{8}. Recognize that 14a\frac{1}{4}a and 24a\frac{2}{4}a are like terms since they both involve the variable aa.

Combine these terms:

14a+24a=34a\frac{1}{4}a + \frac{2}{4}a = \frac{3}{4}a

Step 2: Look at the constant terms 18+38\frac{1}{8} + \frac{3}{8}. Since these fractions have a common denominator, add them directly:

18+38=48=12\frac{1}{8} + \frac{3}{8} = \frac{4}{8} = \frac{1}{2}

Combine all the terms together to form the simplified expression:

34a+13x+12\frac{3}{4}a + \frac{1}{3}x + \frac{1}{2}

Therefore, the solution to the problem is 34a+13x+12 \frac{3}{4}a + \frac{1}{3}x + \frac{1}{2} .

Answer

34a+13x+12 \frac{3}{4}a+\frac{1}{3}x+\frac{1}{2}

Exercise #16

38a+149b+119b+68a=? \frac{3}{8}a+\frac{14}{9}b+1\frac{1}{9}b+\frac{6}{8}a=\text{?}

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Group and simplify terms with the same variable.
  • Step 2: Convert any mixed numbers to improper fractions.
  • Step 3: Find a common denominator to combine fractions.
  • Step 4: Simplify the expression.

Let's work through the steps:
Step 1: Start by grouping like terms. The expression is:
38a+68a+149b+119b \frac{3}{8}a + \frac{6}{8}a + \frac{14}{9}b + 1\frac{1}{9}b .
Step 2: Convert the mixed number to an improper fraction. For 119b 1\frac{1}{9}b : 119b=109b 1\frac{1}{9}b = \frac{10}{9}b .
Rewrite the expression: 38a+68a+149b+109b \frac{3}{8}a + \frac{6}{8}a + \frac{14}{9}b + \frac{10}{9}b .
Step 3: Combine the a a -terms and b b -terms separately:
The a a -terms: 38a+68a=(38+68)a=98a \frac{3}{8}a + \frac{6}{8}a = \left(\frac{3}{8} + \frac{6}{8}\right)a = \frac{9}{8}a .
For the b b -terms: 149b+109b=(149+109)b=249b \frac{14}{9}b + \frac{10}{9}b = \left(\frac{14}{9} + \frac{10}{9}\right)b = \frac{24}{9}b .
Simplify 249 \frac{24}{9}: 249=83 \frac{24}{9} = \frac{8}{3} after dividing by the greatest common divisor 3.
Step 4: Combine simplified terms: 98a+83b \frac{9}{8}a + \frac{8}{3}b .
Convert 98a \frac{9}{8}a to a mixed number: 98a=118a \frac{9}{8}a = 1\frac{1}{8}a .
Convert 83b \frac{8}{3}b to a mixed number: 83b=223b \frac{8}{3}b = 2\frac{2}{3}b .
Thus, the simplified expression is: 118a+223b 1\frac{1}{8}a + 2\frac{2}{3}b .

Therefore, the solution to the problem is 118a+223b 1\frac{1}{8}a + 2\frac{2}{3}b .

Answer

118a+223b 1\frac{1}{8}a+2\frac{2}{3}b