5x^2-12=88 solve algebraically

x = 2sqrt(5)   or   x = -2sqrt(5)

Step-by-step explanation:

5x^2 - 12 = 88

5x^2 = 100

x^2 = 20

x = +/- sqrt(20)

x = 2sqrt(5)   or   x = -2sqrt(5)

area of part 1:

a1=base*height/2=(8+2)*(8-2-2-1)/2=10*3/2=15 ft^2

area of part 2:

a2=length*width=(8+2)*1=10 ft2

area of part 3:

a3=length*width=8*2=16 ft2

total shaded area : a1+a2+a3=41 ft2

total area of the reactangle : a=16*8=128 ft2

total area of the nonshaded region : 128-41=87 ft2