2
Answer: CSet 4: Linear Functions (Intermediate)
Explanation
PROBLEM
If f(x) = 7x - 21, find x when f(x) = 0.
If f(x) = 7x - 21, find x when f(x) = 0.
A.
0
B.
21
C.✓ Correct
3
D.
7
Detailed Explanation
Choice C is the best answer. 7x - 21 = 0. x = 3
Why others are wrong:
A: 0 is incorrect because it does not satisfy the equation.
B: 21 is incorrect because it does not satisfy the equation.
D: 7 is incorrect because it does not satisfy the equation.