Three times x is 13 less than y. The sum of x and two times y is 12. Write two equations and graph to find the value of y.

Question

I really don't understand this practice question.

Answer 1

3x = y - 13        3x + 13 = y

x + 2y = 12

x + 2(3x + 13) = 12

x + 6x + 26 = 12
7x = -14

x = -2

y = 3(-2) + 13

y = 7