Yis inversely proportional to the square of x. A table of values for x and y is shown.

a) Express y in terms of x.
b) Work out the positive value of x when y = 25

(a)

(b)

Step-by-step explanation:

Given

Variation: Inverse proportional.

This is represented as:

See attachment for table

Solving (a):

First convert variation to equation

From the table:

So, we have:

Substitute 4 for k in

Solving (b): x when y = 25.

Substitute 25 for y in

Cross Multiply

Divide through by 25

Take positive square roots of both sides

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

step-by-step explanation: