Question

Find the replacement
15 - x = 9
A) 5
B) 6
C) 7
D) 8

Answer 1

what do you need to do to isolate x to one side of the equation?

Answer 2

Answer 6 @Fishy1237

Answer 3

Why don't you simply try each number as a replacement for x?

Find the replacement
15 - x = 9
A) 5
B) 6
C) 7
D) 8

15 - 5 = 9 ? Wrong, 15-5 = 10
15 - 8 = 9 ? Wrong, 15-8 = 7

Your fastest way of answering the question is to pick the right answer, the one that makes

15 - ___ = 9

What did you get?