2x - 3y = -13, y = 2x + 7
2007-08-12 13:48:11 · 4 answers · asked by jusjay30 1 in Science & Mathematics ➔ Mathematics
2x - 3y = - 13
2x - y = - 7
2x - 3y = - 13
- 2x + y = 7---ADD
-2y = - 6
y = 3
2x - 9 = - 13
2x = - 4
x = - 2
x = - 2 , y = 3
2007-08-12 22:51:45 · answer #1 · answered by Como 7 · 1⤊ 0⤋
2x - 3y = -13
-2x + y = 7
Add the two equations, u'll get,
2x - 2x - 3y + y = -13 + 7
-2y = -6
y = 3
x = 1/2 (y - 7)
x = 1/2 (3 - 7)
x = -2
(-2, 3) is the solution
2007-08-12 20:54:31 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Substitute 2x+7 for y, giving 2x-3(2x+7)=-13
simplify to -4x-21=-13
x=-2
y=3
2007-08-12 20:54:57 · answer #3 · answered by A T 1 · 0⤊ 0⤋
2x-3(2x+7)=-13
2x-6x-21=-13
-4x-21=-13
-4x=8
x=-2
y=(2*-2)+7
y=3
2007-08-12 20:56:04 · answer #4 · answered by bradlelf 2 · 0⤊ 0⤋