It takes Trevon ten hours to clean an attic. Cody can clean the same attic in seven
hours. Find how long it would take them if
they worked together.

Ithink the answer is b.

You move the constant to the right side and change its sign to be 9z= -6 -8. that’s the first step.the second step would be calculate the difference of -8-6 to get -14. you equation should now be 9z=-14the last step is to divide both sides by 9 to get z=-14/9hope this

90