What type of function is f(x) = 2x + 3

It is a positive linear function.

Step-by-step explanation:

If you were to graph the equation, it would show up as a diagonal line raising from the negative end of the graph to the positive end. This is because it contains a positive number being multiplied by x, making the function positive, and it contains no exponent, making it linear.

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