Surface areas geometry help :)

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

What happens to the area as the sliders are adjusted? what do you think the formula for the area of a triangle is divided by 2?

How to find the exponential function y=ca^x, with points (1,2) and (2,1)