Please help easy math question

A rectangular carte has the dimensions shown, in metres. The height is 2x, the width is x, and the length is 2x+2. a) What is the expression for the total surface of the crate (Please explain how to get this answer) b) What is an expression for the volume of the crate (i dont get it)

a) Surface area of a rectangular prism = 2ab + 2bc + 2ac
In this case,
a = 2x + 2
b = 2x
c = x

So, substituting these in we get;
2*(2x + 2)*2x + 2*2x*x + 2*(2x+2)*x [EXPAND]
= 8x^2 + 8x + 4x^2 + 4x^2 + 4x [SIMPLIFY]
= 16x^2 + 12x

I hope that made sense :)

b) This is asking for the volume of the rectangular prism
V = abc

Substitute the same values as before;
V = (2x + 2)*2x*x [EXPAND AND SIMPLIFY]
V = 4x^3 + 4x^2



I hope I helped! :)

a) 2(h*w)+2(h*l)+2(h*w)=surface area
2(2x*x)+2(2x*(2x+2))+2(x*(2x+2)= surface area

the carte has 6 surfaces. to get the surface area of a rectangle you multiply length by width (or height by width or height by length). Each of the opposite sides of the carte are going to have the same surface area, so you simply multiply each of those by 2 and add all three values together to get the total suface area.

b)w*l*h= area of carte
x*(2x+2)*2x= area of carte

a) rectangular crate has 4 surfaces. 2 of them are equal to each other ,the other two are equal too but not equal to the first pair....just look at the picture you'll understand

S(surface) = 2 * 2x * x + 2 * x*(2x+2) = ...

b)
volume is length*width*height=2x*x*(2x+2) = ...


do the basic calculations