Question

(i) 7x -- 42
(iv) - 16 z + 20 z3​

Answer 1

Answer:

7x - - 42

= two different variables can be subtracted

Answer 2

Explanation:

(1) 7x=42

X=42÷7

X=6

(2) -16z+20z3=0

20z3=16

Z3=16÷20

z3=4/5

z3=(0.8)3

z=0.8×0.8×0.8

z=0.512

I hope it is helpful for you