I hate questions that use unknowns and ask you to say which ones represent areas.

Here are some expressions
(a+b)c
ac+b
2abc
πa^2 + πb^2
2πc

The letters a,b and c represent lengths. π(pi) and 2 are numbers that have no dimentions.

Two of the expressions could represent areas, which two?

AH! Do you see why im stuck!?!

2. Originally Posted by L0T3X
I hate questions that use unknowns and ask you to say which ones represent areas.

Here are some expressions
(a+b)c
ac+b
2abc
πa^2 + πb^2
2πc

The letters a,b and c represent lengths. π(pi) and 2 are numbers that have no dimentions.

Two of the expressions could represent areas, which two?

...
The product of 2 lengths yields an area. You only have to look if you have an expression where 2 lengths are multiplied:

$\displaystyle \bold{(a+b) \cdot c}$ is obviously an area

ac +b is the sum of an area and a length, that means no single area.

2abc is a volume

$\displaystyle \bold{\pi a^2+\pi b^2}$ is the sum of 2 areas (of circles), that means it is an area too.

$\displaystyle 2 \pi c$ is a length (the circumference of a cicle with radius c)