# Doing some more polynomials and word problems

• Sep 15th 2011, 01:41 AM
Graem
Doing some more polynomials and word problems
now the equations I think I know What to do, I just need to be sure im right.

The word problems is what im having trouble with. In which you got to change the sentence into a math problem.

Okay polynomials First

This problem I think I know what to do

5(x+3)+2(x-1)

So I use the 5 and 2 to multiply the numbers in the bracket

so it be this

5x+15+2x-2

7x + 13

Its word problems is what im having trouble

So heres the first sentence

"the sum of two numbers is 44 and one of the numbers is 12 more than the other. find the numbers"

So is it like
44=44
12

or something like that? I be so happy if you can help me with this.
• Sep 15th 2011, 03:08 AM
skeeter
Re: Doing some more polynomials and word problems
Quote:

"the sum of two numbers is 44 and one of the numbers is 12 more than the other. find the numbers"
two numbers where one is 12 more than the other ... x and (x+12)

their sum is 44

finish it
• Sep 15th 2011, 03:11 AM
HallsofIvy
Re: Doing some more polynomials and word problems
NO. You should have two equations, since there are two facts stated here and you should have letters, representing the numbers in your equations. After all, if you are going to "find the numbers", you have to have them in the equations! Oh, and 44/12 is NOT equal to 44.

You have to give names to the two- x and y are "traditional" but you can use any letters you like. I recommend you write out explicitely "let x be the larger number and y the smaller number". "The sum of two numbers is 44". Okay the sum of two numbers, x and y, is x+ y. Set that equal to 44. "One of the numbers is 12 more than the other". If x is the larger number, then x= y+ 12. Solve those two equations for x and y.Notice that, because the second equation is "x= y+ 12", you can replace x in the first equation by y+ 12 leaving you an equation in just y. Solve that for y, then, replacing y with that number, solve for x.