Variables and Algebraic Expressions: Decimal numbers

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

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

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

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

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:

$7.3×4a + 2.3 + 8a =$

29.2a + 2.3 + 8a = 

$37.2a + 2.3$

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.

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

1. Identify and group similar terms:

• Constant term: $7.8$
• Terms with $a$: $3.5a + 3.9a$
• Terms with $b$: $-80b - 7.8b$

2. Simplify each group:

• Combine terms with $a$:
  $3.5a + 3.9a = (3.5 + 3.9)a = 7.4a$
• Combine terms with $b$:
  $-80b - 7.8b = (-80 - 7.8)b = -87.8b$

3. The constant term remains $7.8$.

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

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

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

• Step 1: Simplify the division $39.3 : 4a$.
  To solve $39.3 : 4a$, we treat this as $\frac{39.3}{4a}$.
  Calculating the division: $\frac{39.3}{4} = 9.825$. Therefore, $\frac{39.3}{4a} = \frac{9.825}{a}$.
• Step 2: Rearrange the terms.
  We now have $\frac{9.825}{a} + 5a + 8.2 + 13z$. 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 $13z + 8.2 + \frac{9.825}{a} + 5a$.

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

To solve this problem, follow these steps:

• Step 1: Identify Like Terms

The expression is $5.6x + 7.9y + 53xy + 12.1x$. Here, $5.6x$ and $12.1x$ are like terms.

• Step 2: Combine Like Terms

Add the coefficients of $x$: $5.6x + 12.1x = (5.6 + 12.1)x = 17.7x$.

• Step 3: Write the Simplified Expression

After combining the like terms, we get:

$17.7x + 7.9y + 53xy$

This is the simplified form of the expression.

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