Aleak in a pool causes the height of the water to decrease by 0.25 foot over 2 hours. after the leak is fixed, the height of the water is 4.75 feet. the equation 4.75 = x +(-0.25) can be used to find x, the original height of the water in a pool.

The original height of the water level in pool is 5 feet

Given that , A leak in a pool causes the height of the water to decrease by 0.25 foot over 2 hours.  

After the leak is fixed, the height of the water is 4.75 feet.  

The equation 4.75 = x + (- 0.25) can be used to find x, the original height of the water in a pool.

So by solving the given equation and finding value of "x" gives the original height of water in pool

We have to find the original height of the water level in the tank.

So, let us solve the given equation

Hence, the original height of the water level is 5 feet

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