Answer:
c = -4
Step-by-step explanation:
Solve for c:
3 c + 15 = c + 7
Subtract c from both sides:
(3 c - c) + 15 = (c - c) + 7
3 c - c = 2 c:
2 c + 15 = (c - c) + 7
c - c = 0:
2 c + 15 = 7
Subtract 15 from both sides:
2 c + (15 - 15) = 7 - 15
15 - 15 = 0:
2 c = 7 - 15
7 - 15 = -8:
2 c = -8
Divide both sides of 2 c = -8 by 2:
(2 c)/2 = (-8)/2
2/2 = 1:
c = (-8)/2
The gcd of -8 and 2 is 2, so (-8)/2 = (2 (-4))/(2×1) = 2/2×-4 = -4:
Answer: c = -4
