I am working on system of equations, and I am totally lost, every time I do it it turns out really wrong. Could some one help explain this to me.
Find the vaules of x and y that solve the following systems of equations:
-7x+9y=-2
-3x+2y=1
Thanks!
I am working on system of equations, and I am totally lost, every time I do it it turns out really wrong. Could some one help explain this to me.
Find the vaules of x and y that solve the following systems of equations:
-7x+9y=-2
-3x+2y=1
Thanks!
there are two main ways to do problems like these. there is elimination and substitution. i will describe elimination, since it is generally what i prefer to do
first we want to get the coefficient of one of the variable the same in magnitude in both equations. then we can add or subtract one equation from another (depending on signs) to eliminate that variable. once we get rid of that variable, only one of the variables are left which we can easily solve for. we solve for it, and then use it to find the other variable that we eliminated originally.
let's say we want to eliminate the x's
first step, multiply equation (1) by 3, and equation (2) by -7
what to you get?
you need to review how to solve equations. your solution is again wrong. the correct answer is: x = -1. now use that to find y
(you can check your answer you know. when you got x = 18/13, why didn't you plug it into the left hand side of the (red) equation and see if you actually got -2 as the answer?)