### Home > MC1 > Chapter 10 > Lesson 10.1.2 > Problem 10-25

10-25.

If 4*k* + 1 = −7, then 4*k* = −8.

Why does this make sense?

If 4*k* = −8, what must *k* be equal to?

Try setting up a diagram to figure it out.

*k* = −2

What do you need to subtract from 30 to get 10?

How can you use this to help figure out the value of *x*?