Question

Given that f(x)=2x-5, find the value of x that makes f(x)=15
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Answer 1

x = 10

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

1. Brackets
2. Parenthesis
3. Exponents
4. Multiplication
5. Division
6. Addition
7. Subtraction

• Left to Right

Algebra I

• Functions
• Function Notation

Explanation:

Step 1: Define

f(x) = 2x - 5

f(x) = 15

Step 2: Solve for x

1. Substitute in f(x) [Function]: 15 = 2x - 5
2. [Addition Property of Equality] Add 5 on both sides: 20 = 2x
3. [Division Property of Equality] Divide 2 on both sides: 10 = x
4. Rewrite: x = 10