Question

use the elimination method to solve.
a+7b=13
a+2b=-2

Is there a solution

Are there infinetly many soutions

Or is there no solution

Answer 1

did you try the method of elimination?

Answer 2

ubtract the bottom equation from the top equation, then solve for b and then plug the value you get back into either equation

Answer 3

if you try the method of elimination and it works for finding the unknown, then there are two ways in doing so

Answer 4

Let's eliminate a since the coefficient of a is the same in both equation.

a + 7b = 13
-a + 2b = -2
-------------
5b = 15
b = 3

Plug in b = 3 in to one of the equations and solve for a:

a + 7(3) = 13
a = 13 - 21
a = -8

Therefore, b = 3 and a = -8

Answer 5

Thanks genius12! just beginning algebra1 at the age of 40 and have no clue as to what i'm doing. I'll use this as notes, it looks fairly easy.

Answer 6

Medal? @taepoohwae

Answer 7

tae, just so you don't get confused what he wrote should be written as
a+7b=13
-(a+2b)= -(-2) which becomes -a-2b = 2

Answer 8

Thanks looking through my textbook I've noticed those also.