4. What value of x makes this equation true?

Answer:
x = -30
Step-by-step explanation:
Combine like terms. Subtract 0.1x from both sides; the result is 0.5x + 7 = -8. Next, subtract 7 from both sides, obtaining:
0.5x = -15
Dividing both sides by 0.5 results in x = -30
The equation is true for x = -30