Question

Tobin is solving the equation 3(x - 1.25) = 11.25. His work is shown below.

What mistake did Tobin make?

a
Tobin did not make a mistake.
b
Tobin should have subtracted 3.75 from each side.
c
Tobin did not distribute the 3 correctly.
d
Tobine should have divided by 3.

Answer 1

D. Tobin did not make a mistake

Explanation:

i just did it on ed

Answer 2

D

Explanation:

If you take a look at everything up to the step before last, you can follow the train of thought and see that Tobin did everything correctly. However, when he had 3x=15 and multiplied both sides by 3, he got a ridiculous answer. If he had instead divided both sides by 3, he would have found that x=5, and not 135. Therefore, the correct answer is D.