Y = x + 4
Slope = 1
Y-intercept = 4
10(y+2)-y=2(9y-8)
Mutiply the first bracket by 10
Mutiply the second bracket by 2
(10)(y)(10)(2)= 10y+20
(2)(9y)(2)(-8)= 18y-16
10y+20-y= 18y-16
10y-y+20= 18y-16
9y+20= 18y-16
move 18y to the other side
sign changes from +18y to -18y
9y-18y+20= 18y-18y-16
-9y+20= -16
move +20 to the other side
sign changes from +20 to -20
-9y+20-20=-16-20
-9y= -36
divide by -9
-9y/-9= -36/-9
y= 4
Answer: y= 4
For similar figures, the ratio of areas is the square of the ratio of linear dimensions. The smaller billboard requires
.. (4/5)^2 * 250 ft^2 = 160 ft^
of material.