The amount of water that is needed to fill the pool is equal to the volume of the pool.
The pool is rectangular, with uniform depth so the volume of pool will be the product of its length , width and depth.
Thus,
Volume = 25 x 18 x 6 = 2700 ft³
This means, 2700 ft³ water is needed to fill the pool.
Simplify 1/4x to x/4
-x/4 - 14y - 1/8x + 2y + 18
Simplify 1/8x to x/8
-x/4 - 14y - x/8 + 2y + 18
Collect like terms
(-x/4 - x/8) + (-14y + 2y) + 18
Simplify
-3/8x - 12y + 18
