### Home > CC4 > Chapter A > Lesson A.1.7 > Problem A-72

A-72.

Is

*x*= −4 a solution to 3*x*+ 7 =*x*− 1?If −2

*x*− 4 = −4*x*+ 3, then does*x*= 3?Is

*x*= 2 a solution to −3*x*+ 5 + 5*x*− 1 = 0?If

*f*(*x*) = −(*x*− 1) then does*f*(−2) = 3?

Substitute the possible answer in for *x*.

3( −4 ) + 7 = ( −4 ) − 1

If the numbers on both sides of the equation sign are true, then the possible answer is correct.

−12 + 7 = −5

−5 = −5

Yes

Follow the steps in part (a).

No

Follow the steps in part (a).

How does the negative in front of the parentheses change what is inside?

Follow the steps in part (a).