What does the statement T(20) = T(c) mean?

What is the value of  y  in the solution to the system of equations? x  +  y  =  12x  –  3y  =  –30a. –8b. –3c. 3d. 8

Although changes result from business transactions, the equality of the fundamental bookkeeping equation must remain. t/f

The spotter on the ground is standing beneath the safety net. what is his distance from the base of the platform, to the nearest meter? 3 meters, 2 meters, 4 meters, 1 meter?