solve the system if equations by using the elimination-by-addition method
5x + 2y = -4
5x - 3y = 6
2007-12-15 12:50:51 · 3 answers · asked by CBrizz8807 1 in Science & Mathematics ➔ Mathematics
subtract the second equation from the first
(5x + 2y) - (5x - 3y) = (-4) - (6)
5y = -10
y= -2
solve for x with y= -2
5x + 2(-2) = -4
x=0
If you don't understand adding equations, think about it this way:
if you were solving a normal equation, you could add, subtract, multiply, or divide and still keep the two sides equal, as long as you do the same thing to both sides.
Here, you're also subtracting the same thing from both sides, because (5x - 3y) = 6. You're just subtracting a different form of the same thing from different sides.
2007-12-15 12:55:47 · answer #1 · answered by Anonymous · 0⤊ 0⤋
y = -2 and x=0
2007-12-15 15:50:43 · answer #2 · answered by analyn 3 · 0⤊ 0⤋
5x + 2y = -4
-5x + 3y = -6
5y = -10
y = -2
5x + 2(-2) = -4
5x - 4 = -4
5x = 0
x = 0
2007-12-15 12:56:00 · answer #3 · answered by norman 7 · 0⤊ 0⤋