Answer:
x = 14
Step-by-step explanation:
Solve for x:
90 = -4 + 2 x + 3 (x + 8)
3 (x + 8) = 3 x + 24:
90 = 3 x + 24 + 2 x - 4
Grouping like terms, 3 x + 2 x - 4 + 24 = (2 x + 3 x) + (-4 + 24):
90 = (2 x + 3 x) + (-4 + 24)
2 x + 3 x = 5 x:
90 = 5 x + (-4 + 24)
24 - 4 = 20:
90 = 5 x + 20
90 = 5 x + 20 is equivalent to 5 x + 20 = 90:
5 x + 20 = 90
Subtract 20 from both sides:
5 x + (20 - 20) = 90 - 20
20 - 20 = 0:
5 x = 90 - 20
90 - 20 = 70:
5 x = 70
Divide both sides of 5 x = 70 by 5:
(5 x)/5 = 70/5
5/5 = 1:
x = 70/5
The gcd of 70 and 5 is 5, so 70/5 = (5×14)/(5×1) = 5/5×14 = 14:
Answer: x = 14
