3x=2y-5
y-5x=neg.1
2006-06-10 03:34:08 · 4 answers · asked by lovinmymatt 2 in Science & Mathematics ➔ Mathematics
Solve,
3x = 2y - 5 ... (1)
y - 5x = -1 ... (2)
Rearrange (2), we get,
y = 5x - 1 ... (3)
Substitute (3) into (1)
3x = 2(5x - 1) - 5
3x = 10x - 2 - 5
3x = 10x - 7
10x - 3x = 7
7x = 7
x = 1 ... (4)
Substitute (4) into (3)
y = 5(1) - 1
y = 4
Therefore x = 1 and y = 4.
2006-06-10 03:46:33 · answer #1 · answered by ideaquest 7 · 0⤊ 0⤋
y=-1+5x (1) (Solving for y)
3x=2(-1+5x)-5 Substituting (1) into the other equation
3x=-2+10x-5
3x-10x=-2-5
-7x=-7
x=1
so, y=-1+5(1)
y=4
2006-06-10 10:56:01 · answer #2 · answered by gari 3 · 0⤊ 0⤋
Here's a hint:
For the second equation ( y - 5x = -1), move the 5x over to the other side. Then you should have y = to something. You can substitute that back into the first formula and go from there, just like in the last question you posted about substitution.
2006-06-10 10:39:48 · answer #3 · answered by Anonymous · 0⤊ 0⤋
3x = 2y - 5
y - 5x = -1
y - 5x = -1
y = 5x - 1
3x = 2(5x - 1) - 5
3x = 10x - 2 - 5
3x = 10x - 7
-7x = -7x
x = 1
y = 5x - 1
y = 5(1) - 1
y = 5 - 1
y = 4
x = 1 and y = 4
2006-06-10 13:24:41 · answer #4 · answered by Sherman81 6 · 0⤊ 0⤋