Expand the polynomial: (−a+b)(b–a)

a^2 - 2ab + b^2

Step-by-step explanation:

Step 1:  Foil

(-a + b)(b - a)

(-a * b) + (-a * -a) + (b * b) + (b * -a)

-ab + a^2 + b^2 - ab

a^2 - 2ab + b^2

 a^2 - 2ab + b^2

a² - 2ab + b²

Step-by-step explanation:

(-a+b)(b-a)

(b-a)(b-a)

(b-a)²

b² - 2ab + a²

Or

a² - 2ab + b²

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

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step-by-step explanation: