Answer:
You don't really need to do it, but it helps you keep things more organized and easier to follow. Imagine if you're doing some multi-variable equation,
2a + 5b + 4d + 3c + b + a + 2d
that looks like a mess, it'll be easier to look at if you put all the similar variables next to each others like this:
a + 2a + b + 5b + 3c + 2d + 4d
(a + 2a) + (b + 5b) + 3c + (2d + 4d)
now you can add them up much easier.
Answer: Each student should raise $225
Step-by-step explanation:
$12,500-$1,250= $11,250
$11,250/50= $225
Check answer:
$225x50= $11,250
The perimeter is (2 lengths) + (2 widths). Since the perimeter is 18 inches, (1 length) + (1 width) must add up to 9 inches.
If the length and the width must both be whole numbers, the only possible choices for the side lengths of this rectangle are:
1 x 8 in
2 x 7 in
3 x 6 in
4 x 5 in .
Answer:
I think the answer would be 
Step-by-step explanation: