I’m really confused can someone explain 8 and 9

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

Evaluate the expression. (9 + 5)(3 + 2)0

The given diagram shows the parts of a right triangle with an altitude to the hypotenuse. using the two given  measures, find the other four.