Question

Can someone help me do this problem and explain it to me step by step? If so I’ll mark you brainliest

Answer 1

Answer:

-21

28

Step-by-step explanation:

1) if r = -4

Substitute r = -4 in 3r - 9

= 3 * (-4) - 9

= -12 - 9

= -21

2) ( 4 / 7 ) * x = 16

 4 * x = 16 * 7

 x = 4 * 7

 x = 28