Please help (math) i just don’t understand

What is the value of x? enter your answer in the box. (cm)

The length of a rectangle is x times the square root of 100. the width is one-half y more than three-halves x. given that the area of the rectangle is 125 cm2, which equation could represent the rectangle in terms of x and y? a) 5xy − 15x = 125 b) 5xy + 15x = 125 c) 15x2 − 5xy = 125 d) 15x2 + 5xy = 125

You receive 15% of the profit from a car wash how much money do you receive from a profit of 300