12d - 9 = 15d + 9

5 answers

Please check your problem again. It looks like you have an error.
OOps! My error.

12d - 9 = 15d + 9

12d - 15d = 9 + 9

-3d = 18
d = -6
how to solve -6r-5=7-12r
r+2
r=2