If r varies directly as w and the constant of variation is 12 what is the value of w when r =42

Consider the proof. given: segment ab is parallel to line de. prove: what is the missing statement in step 5?

After t seconds, a ball tossed in the air from the ground level reaches a height of h feet given by the equation h = 144t-16t^2. after how many seconds will the ball hit the ground before rebounding?

What ia the sum if the first 7 terms of the geometric series