The equation is already is slope intercept form where you can easily point out the gradient, or the slope, and the y intercept.
y=mx+b where m is the gradient, and b is the y intercept.
Since there is no m, the gradient is 1.
The y intercept had x=0 and y=b
b in this case is 6
the y intercept= (0,6)
I got 6x+3
The three equations are:
(2x-6) + (3x+1) + (x+8) =perimeter
2x+3x+x/1x=6x
-6+1+8= 3
80,000going up by 10% you just add the 10% on
Lola is incorrect because the width is half of the length as stated before.