Question

Jen solved the equation 100 minus one-half x equals 92 to determine the number of questions, x, she answered incorrectly on a test. She began by subtracting 100 from both sides, then multiplying both sides by –2. Which best describes the accuracy of Jen's work?

Answer 1

Answer: C on endg

Explanation:

Answer 2

The options are:

A. Incorrect. She needed to add 100 to both sides instead of subtracting 100.

B. Incorrect. She needed to multiply both sides by –2 first, then subtract 100

C. Correct. She could have also subtracted 100 from both sides, then divided by -2

D. Correct. She could have also multiplied both sides by –2 first, then subtracted 100.

Answer:

C. Correct. She could have also subtracted 100 from both sides, then divided by -2

Explanation:

Given

`100 - (1)/(2)x = 92`

Required

Describe the accuracy in her work

First, she needed to subtract 100 from both sides

`100 -100 - (1)/(2)x = 92-100`

`- (1)/(2)x = -8`

Then multiply through by -2

`-2 * - (1)/(2)x = -8 * -2`

`x = 16`

Hence, option (c) is correct.