The width is 3m because 3*7 is 21m^2. Also they said the length is 4 more than the width (3+4=7)
Suppose the length of each side of the cube is x, so the volume must be:
x^3.
If the volume is 15 cm^3, so the length must be cuberoot(15) which is not integer,. So, the volume of the cube with integer side never equal with 15 cm^3
I think the equation is y= -1/3x+1. The slope is going down, so it’s negative. And the y intercept is 1. And how I got a fraction is by using rise/run.
I'm assuming the answer would be D.
Hope this helped! :D