Question

Use an equation to solve the problem.

The difference between a number and 4 times that number is -21. What is the number?

Answer 1

x-4x=-21
-3x=-21 (like terms)
3x=21 (negate both sides)
x=7

Answer 2

Let, the number = x
It is given that, 4x - x = -21
3x = -21
x = -21/3
x = -7

In short, Your Answer would be: -7

Hope this helps!