SOLUTION: Solving for... 4x-3y = 10 x+4y = 7 Using any methood... Solution: x = 3.21052631578947, y = 0.947368421052632 However (1, -2) also works why? How can I solve this system

 

Hi, Re:Your TY

(1, -2) 4x-3Y=10 or 4*1+3*2=10 4+6=10  Yes

x+4y=7 or 1+4*(-2)=7   1+(-8)=7  No:  -7 ≠ 7

Might Check Your Sign in EQ II:  would yield the solution (1,-2) , y = -2 and x = 1

I.  4x-3y = 10

II. x+4y = 7              ||Signs SO important to the Solution

   4x-3y = 10

  -4x-16y = -28

     -19y = -18

        y = 18/19 = 0.947368421052632  and  x = 3.21052631578947

(1,-2) is a Pt on the fist line, not the 2nd line. The Solution for this system

of Two EQ, is as You found: x = 3.21052631578947, y = 0.947368421052632