I think the most appropriate answer would be "-6.58".
I hope it helped you!
First, change it into general form(y=my+b).
3y=6x-1+10
3y=6x+9
y=2x+3
So, the slope is 2, and the y-intercept is 3
Isosceles triangle has 2 sides that are the same length. So what you have is three sides that measure: x, x, and (x-8). 70 = x + x + (x-8).
70 = x + x + x - 8
78 = 3x
x = 26.
and 26 - 8 = 18.
So two of your sides are 26 inches and the last side is 18 inches.