Answer:
n = -13
Step-by-step explanation:
19 + 10n = 7n - 20
Subtract 7n from each side
19 + 10n-7n = 7n-7n - 20
19+3n = -20
Subtract 19 from each side
19+3n -19 = -20-19
3n = -39
Divide each side by 3
3n/3 = -39/3