How do you solve and check : 0.6 - 0.3(20+x) = 0.75(20)?

1 Answer
May 9, 2018

x = -68

Explanation:

0.6 - 0.3(20 + x) = 0.75(20)

Use the Distributive Property:
0.6 - 0.3(20 + x) = 0.75(20)
0.6 - 6 - 0.3x = 15

Combine Like Terms:
0.6 - 6 - 0.3x = 15
-5.4 - 0.3x = 15

Use the Additive Inverse:
-5.4 - 0.3x = 15
-0.3x = 20.4

Use the Multiplicative Inverse:
-0.3x = 20.4
x = -68

Check:
0.6 - 0.3(20 + x) = 0.75(20)
0.6 - 0.3(20 + (-68)) = 0.75(20)
0.6 - 0.3(-48) = 15
0.6 + 14.4 = 15
15 = 15