26.4k views
2 votes
2. Evaluate (3x + 8) – (2x + 7) when x = 3. 11 1 4 18

User Tassock
by
2.9k points

2 Answers

5 votes

Answer: 4

Explanation:

Step 1: Write out expression

(3x + 8) - (2x + 7)

Step 2: Distribute negative

3x + 8 - 2x - 7

Step 3: Combine like terms

x + 1

Step 4: Substitute

3 + 1 = 4

User Jissell
by
3.7k points
0 votes

Answer: 4

Concept:

Here, we need to understand the idea of evaluation.

When encountering questions that gave you an expression with variables, then stated: "If x = a, y = b, z = c" (a, b, c are all constants), this means you should substitute the value given for each variable back to the expression.

Solve:

Given information

x = 3

Given expression

(3x + 8) - (2x + 7)

Substitute values in the expression

=(3 (3) + 8) - (2 (3) + 7)

Simplify by multiplication in parentheses

=(9 + 8) - (6 + 7)

Simplify by addition

=17 - 13

Simplify by subtraction

=
\boxed{4}

Hope this helps!! :)

Please let me know if you have any questions

User Tonylo
by
3.1k points