2x - 2y = -2
-1(2x - 2y = -2)
2(-x - y = -7)
-2x - 2y = 2
-2x - 2y = -14
4/4y = 16/4
y = 4
2x - 2(4) = -2
2x - 8 = -2
2x = -2 - 8
2x/2 = -10/2
x = -5
2007-02-21 01:11:42 · 2 answers · asked by Rocstarr 2 in Science & Mathematics ➔ Mathematics
Your answer is wrong.
your answer : x = -5, y = 4
When you substitute into the equation,
2x - 2y = 2(-5) - 2(4) = -10 - 8 = -18 <> -2 !!!
The correct method is
2x - 2y = -2
-1(2x - 2y = -2)
2(-x - y = -7)
-2x + 2y = 2 ---(you do wrong in this step)
-2x - 2y = -14
4y/4 = 16/ 4
y = 4
2x - 2(4) = -2
2x - 8 = -2
2x = -2 + 8 ---(you do wrong in this step)
2x/2 = 6/2 ---(next step you do is wrong)
x = 3 ---(your answer is wrong)
Now, check
2x - 2y = 2(3) - 2(4) = 6 - 8 = -2 !!!
-x - y = -(3) - (4) = -7!!!
2007-02-21 02:52:46 · answer #1 · answered by seah 7 · 1⤊ 0⤋
Absolutely and perfectly correct.
2007-02-21 09:24:10 · answer #2 · answered by Ross Taylor 2 · 1⤊ 1⤋