It is known that Y1 = 4x + 8, y2 = 3x-7 When x takes what value, Y1 and Y2 are opposite to each other

It is known that Y1 = 4x + 8, y2 = 3x-7 When x takes what value, Y1 and Y2 are opposite to each other

When Y1 and Y2 are opposite to each other, Y1 + y2 = 0
4x+8+3x-7=0
7x+1=0
x=-1/7