SOLUTION: Help please I don't understand 0.5x + 0.4y = -1 0.3x + 0.6y = -0.6

Algebra ->  Systems-of-equations -> SOLUTION: Help please I don't understand 0.5x + 0.4y = -1 0.3x + 0.6y = -0.6      Log On


   

Question 96283: Help please I don't understand
0.5x + 0.4y = -1
0.3x + 0.6y = -0.6
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
.5X+.4Y=-1 MULTIPLY THIS EQUATION BY -.3 (-.15X+.12Y=.3)
.3X+.6Y=-.6 MULTIPLY THE SECOND EQUATION BY .5 (.15X+.3Y=-.3) NOW ADD THESE 2 EQUATIONS.
-.15X+.12Y=.3
.15X+.3Y=-.3
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.42Y=0
Y=0 ANSWER.
.5X+.4*0=-1
.5X=-1
X=-1/.5
X=-2 ANSWER.
PROOF
.3*-2+.6*0=-.6
-.6=-.6