Examples with solutions for Solving an Equation by Multiplication/ Division: Rearranging Equations

Exercise #1

Solve for X:

3x+6=12 3x + 6 = 12

Video Solution

Step-by-Step Solution

Step-by-step solution:

1. Start with the equation: 3x+6=12 3x + 6 = 12

2. Subtract 6 from both sides: 3x+66=126 3x + 6 - 6 = 12 - 6 , which simplifies to 3x=6 3x = 6

3. Divide both sides by 3 to solve for x: x=63 x = \frac{6}{3}

4. Simplify the division: x=2 x = 2

Answer

2

Exercise #2

Solve for X:

4x7=x+5 4x - 7 = x + 5

Video Solution

Step-by-Step Solution

To solve forx x , first, get all terms involving x x on one side and constants on the other. Start from:

4x7=x+5 4x - 7 = x + 5

Subtract x x from both sides to simplify:

3x7=5 3x - 7 = 5

Add 7 to both sides to isolate the terms withx x :

3x=12 3x = 12

Divide each side by 3 to solve forx x :

x=4 x = 4

Thus, x x is 4 4 .

Answer

4 4

Exercise #3

Solve for X:

5x+10=3x+18 5x + 10 = 3x + 18

Video Solution

Step-by-Step Solution

To solve the equation 5x+10=3x+18 5x + 10 = 3x + 18 , follow these steps:

1. Subtract 3x 3x from both sides to get:

5x3x+10=18 5x - 3x + 10 = 18

2. Simplify the equation:

2x+10=18 2x + 10 = 18

3. Subtract 10 10 from both sides:

2x=8 2x = 8

4. Divide both sides by 2 2 :

x=4 x = 4

Answer

4

Exercise #4

Solve for X:

5x3=2 5x - 3 = 2

Video Solution

Step-by-Step Solution

Step-by-step solution:

1. Begin with the equation: 5x3=2 5x - 3 = 2

2. Add 3 to both sides: 5x3+3=2+3 5x - 3 + 3 = 2 + 3 , which simplifies to 5x=5 5x = 5

3. Divide both sides by 5 to solve for x: x=55 x = \frac{5}{5}

4. Simplify the division: x=1 x = 1

Answer

1

Exercise #5

Solve for X:

7x3=4x+9 7x - 3 = 4x + 9

Video Solution

Step-by-Step Solution

To solve the equation 7x3=4x+9 7x - 3 = 4x + 9 , follow these steps:

1. Subtract 4x 4x from both sides to get:

7x4x3=9 7x - 4x - 3 = 9

2. Simplify the equation:

3x3=9 3x - 3 = 9

3. Add 3 3 to both sides:

3x=12 3x = 12

4. Divide both sides by 3 3 :

x=4 x=4

Answer

4

Exercise #6

4x7=13 4x - 7 = 13

x=? x = \text{?}

Video Solution

Step-by-Step Solution

To solve the equation 4x7=13 4x - 7 = 13 , follow these steps:

1. Add 7 to both sides: 4x=13+7 4x = 13 + 7

2. Simplify the right side: 4x=20 4x = 20

3. Divide both sides by 4: x=204 x = \frac{20}{4}

4. Solve: x=5 x = 5

Answer

5

Exercise #7

10+9x=91 10+9x=91

How much is X worth?

Video Solution

Step-by-Step Solution

To solve the equation 10+9x=91 10 + 9x = 91 , we'll follow these steps:

  • Step 1: Eliminate the constant term on the left side by subtracting 10 from both sides of the equation.

10+9x10=9110 10 + 9x - 10 = 91 - 10 9x=81 9x = 81

  • Step 2: Solve for x x by dividing each side of the equation by the coefficient of x x , which is 9.

9x9=819 \frac{9x}{9} = \frac{81}{9} x=9 x = 9

Hence, the value of x x is 9 9 .

Answer

9 9

Exercise #8

5x+6=56 5x+6=56

How much is X X worth?

Video Solution

Step-by-Step Solution

To solve the equation 5x+6=56 5x + 6 = 56 , we will follow these steps:

  • Step 1: Subtract 6 from both sides of the equation to eliminate the constant term on the left-hand side.
  • Step 2: Simplify the resulting equation.
  • Step 3: Divide both sides by 5 to isolate x x .

Now, perform each step:

Step 1: Subtract 6 from both sides:
5x+66=566 5x + 6 - 6 = 56 - 6

Step 2: Simplify both sides:
5x=50 5x = 50

Step 3: Divide both sides by 5 to solve for x x :
x=505 x = \frac{50}{5}

Step 4: Simplify the division:

x=10 x = 10

Therefore, the solution to the problem is x=10 x = 10 .

Answer

10 10

Exercise #9

4a+524+a=2a 4a+5-24+a=-2a

a=? a=?

Video Solution

Step-by-Step Solution

To solve the equation 4a+524+a=2a 4a + 5 - 24 + a = -2a , follow these steps:

  • Step 1: Start by combining like terms on the left side of the equation:

4a+a+524=2a 4a + a + 5 - 24 = -2a

This simplifies to:

5a19=2a 5a - 19 = -2a

  • Step 2: Move all terms involving a a to one side of the equation and constant terms to the other side:

Add 2a 2a to both sides to collect all terms with a a :

5a+2a=19 5a + 2a = 19

This simplifies to:

7a=19 7a = 19

  • Step 3: Solve for a a by dividing both sides by 7:

a=197 a = \frac{19}{7}

Thus, the value of a a is 197 \frac{19}{7} , which can be written as a mixed number:

a=257 a = 2\frac{5}{7} .

Upon verifying with the given choices, the correct answer is choice 1: 257 2\frac{5}{7} .

Answer

257 2\frac{5}{7}

Exercise #10

m+3m17m+6=20 m+3m-17m+6=-20

m=? m=\text{?}

Video Solution

Step-by-Step Solution

To solve the problem, we will use the following steps:

  • Step 1: Simplify the equation by combining like terms.
  • Step 2: Isolate the variable m m using algebraic methods.
  • Step 3: Solve for m m and verify the solution.

Let's begin:

Step 1: Simplify the equation m+3m17m+6=20 m + 3m - 17m + 6 = -20 .
Combine the coefficients of m m :

(1+317)m+6=20 (1 + 3 - 17)m + 6 = -20

This simplifies to:

13m+6=20 -13m + 6 = -20

Step 2: Isolate m m .
Subtract 6 from both sides:

13m+66=206 -13m + 6 - 6 = -20 - 6

Simplifies to:

13m=26 -13m = -26

Step 3: Solve for m m by dividing both sides by -13:

m=2613 m = \frac{-26}{-13}

The division simplifies to:

m=2 m = 2

Therefore, the solution to the problem is m=2 m = 2 , which corresponds to choice 2 in the given options.

Answer

2

Exercise #11

Solve for X:

5x+4=7x 5x+4=7x

Video Solution

Step-by-Step Solution

To solve the equation 5x+4=7x 5x + 4 = 7x , we will proceed as follows:

  • Step 1: Subtract 5x 5x from both sides to simplify the equation.

The equation is:
5x+45x=7x5x 5x + 4 - 5x = 7x - 5x

This simplifies to:
4=2x 4 = 2x

  • Step 2: To solve for x x , divide both sides by 2 to isolate x x .

Perform the division:
42=2x2 \frac{4}{2} = \frac{2x}{2}

This gives us:
2=x 2 = x

Therefore, the solution to the equation is x=2 x = 2 .

Answer

2 2

Exercise #12

2+3a+4=0 2+3a+4=0

a=? a=\text{?}

Video Solution

Step-by-Step Solution

To solve the equation 2+3a+4=0 2 + 3a + 4 = 0 , follow these steps:

  • Step 1: Combine the constant terms on the left side.
    The terms 2 2 and 4 4 can be combined to get 6 6 .
    Hence, the equation becomes 3a+6=0 3a + 6 = 0 .
  • Step 2: Isolate the term with the variable a a .
    Subtract 6 6 from both sides to get 3a=6 3a = -6 .
  • Step 3: Solve for a a by dividing both sides by the coefficient of a a , which is 3 3 .
    Thus, a=63=2 a = \frac{-6}{3} = -2 .

Therefore, the solution to the problem is a=2 a = -2 .

Answer

2 -2

Exercise #13

5x+7=32 5x+7=32

Video Solution

Step-by-Step Solution

To solve this linear equation, follow these steps:

  • Step 1: Isolate the term with x x by subtracting 7 from both sides of the equation.
  • Step 2: Perform the subtraction to simplify the equation.
  • Step 3: Divide both sides by 5 to solve for x x .

Let’s perform each step:

Step 1: Subtract 7 from both sides:
5x+77=327 5x + 7 - 7 = 32 - 7

This simplifies to:
5x=25 5x = 25

Step 2: Divide both sides by 5 to isolate x x :
x=255 x = \frac{25}{5}

Perform the division:
x=5 x = 5

Hence, the solution to the equation 5x+7=32 5x + 7 = 32 is x=5 x = 5 .

Answer

x=5 x=5

Exercise #14

8x+4=4 8x+4=4

Video Solution

Step-by-Step Solution

We will solve the given linear equation 8x+4=4 8x + 4 = 4 step-by-step:

Step 1: Subtract 4 from both sides of the equation to begin isolating the variable x x :

8x+44=44 8x + 4 - 4 = 4 - 4

This simplifies to:

8x=0 8x = 0

Step 2: Divide both sides of the equation by 8 to solve for x x :

8x8=08 \frac{8x}{8} = \frac{0}{8}

This results in:

x=0 x = 0

Therefore, the solution to the equation is x=0 x = 0 .

Answer

x=0 x=0

Exercise #15

132x=0 13-2x=0

Video Solution

Step-by-Step Solution

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

  • Step 1: Subtract 13 from both sides of the equation to isolate the term with xx.
  • Step 2: Divide by 2-2 to solve for xx.

Now, let's work through each step:
Step 1: Begin by subtracting 13 from both sides:

132x13=01313 - 2x - 13 = 0 - 13
Which simplifies to:

2x=13-2x = -13

Step 2: Divide both sides by 2-2 to solve for xx:

2x2=132\frac{-2x}{-2} = \frac{-13}{-2}

This simplifies to:

x=132x = \frac{13}{2}

When expressed as a mixed number, xx equals:

x=612x = 6\frac{1}{2}.

Therefore, the solution to the problem is x=612x = 6\frac{1}{2}.

The correct answer choice is :

x=612x = 6\frac{1}{2}

.

Answer

x=612 x=6\frac{1}{2}

Exercise #16

14x6=134 14x-6=134

Video Solution

Step-by-Step Solution

To solve the equation 14x6=134 14x - 6 = 134 , follow these steps:

  • Step 1: Isolate the term involving x x . We do this by adding 6 to both sides of the equation to eliminate the constant term:

14x6+6=134+6 14x - 6 + 6 = 134 + 6

This simplifies to:

14x=140 14x = 140

  • Step 2: Solve for x x by dividing both sides by 14 (the coefficient of x x ):

14x14=14014 \frac{14x}{14} = \frac{140}{14}

This gives us:

x=10 x = 10

Therefore, the solution to the problem is x=10 x = 10 .

Answer

x=10 x=10

Exercise #17

8002xx=803 800-2x-x=803

Video Solution

Step-by-Step Solution

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

  • Step 1: Combine like terms on the left side of the equation.
  • Step 2: Isolate the variable x x on one side of the equation.
  • Step 3: Solve for x x and simplify the result.

Now, let's work through each step:
Step 1: The left side of the equation is 8002xx 800 - 2x - x . Combine the terms with x x :
This becomes 8003x=803 800 - 3x = 803 .

Step 2: Subtract 800 from both sides to isolate the term with x x :
8003x800=803800 800 - 3x - 800 = 803 - 800
This simplifies to 3x=3 -3x = 3 .

Step 3: Divide both sides by -3 to solve for x x :
x=33 x = \frac{3}{-3}
Thus, x=1 x = -1 .

Therefore, the solution to the problem is x=1 x = -1 .

Answer

x=1 x=-1

Exercise #18

20+20x3x=88 20+20x-3x=88

x=? x=\text{?}

Video Solution

Step-by-Step Solution

To solve this problem, we need to find x x in the equation:

20+20x3x=88 20 + 20x - 3x = 88

Step 1: Combine like terms on the left-hand side of the equation. The terms involving x x are 20x 20x and 3x-3x.

20x3x=17x 20x - 3x = 17x

Thus, the equation becomes:

20+17x=88 20 + 17x = 88

Step 2: Isolate the x x -related terms by moving the constant term to the right-hand side. To do this, subtract 20 from both sides:

17x=8820 17x = 88 - 20

17x=68 17x = 68

Step 3: Solve for x x by dividing both sides of the equation by 17:

x=6817 x = \frac{68}{17}

x=4 x = 4

Therefore, the solution to the problem is x=4 x = 4 .

Answer

4 4

Exercise #19

Solve for X:

8x+3=29 -8x+3=-29

Video Solution

Step-by-Step Solution

To solve the equation 8x+3=29 -8x + 3 = -29 , we'll follow these steps:

  • Step 1: Subtract 3 from both sides of the equation to eliminate the constant on the left side.
  • Step 2: Divide both sides by 8-8, the coefficient of xx, to solve for xx.

Let's apply these steps:
Step 1: Subtract 3 from both sides:
8x+33=293-8x + 3 - 3 = -29 - 3
This simplifies to:
8x=32-8x = -32

Step 2: Divide both sides by 8-8 to isolate xx:
8x8=328\frac{-8x}{-8} = \frac{-32}{-8}
This results in:
x=4x = 4

Therefore, the solution to the equation is x=4 x = 4 , which corresponds to choice 4.

Answer

4

Exercise #20

Solve for X:

10+3x=19 10+3x=19

Video Solution

Step-by-Step Solution

To solve the equation 10+3x=1910 + 3x = 19, follow these steps:

  • Step 1: Subtract 10 from both sides of the equation to begin isolating xx:
  • 10+3x10=191010 + 3x - 10 = 19 - 10
  • This simplifies to 3x=93x = 9.
  • Step 2: Divide both sides by 3 to solve for xx:
  • 3x3=93\frac{3x}{3} = \frac{9}{3}
  • This reduces to x=3x = 3.

Therefore, the solution to the problem is x=3x = 3.

Answer

3