Question

Just need help with number 1. Thanks!

Answer 1

Answer:512/27

Explanation:

10x^2+20x-71=9

30x^3=9+71

30x^3=80

x^3=80/30

x^3=8/3

x=8^3/3^3

x=512/27

Answer 2

For 1 you can use 2 or -4, either one works.