2x - 5y = 11
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4x + 10y = 18
.........
I understand how to solve using elimination, but what's throwing me for a loop is the fact that one line has a subtract sign and the second line is an addition sign. I just don't know which one to turn into a negative!
This is what I've been doing, please tell me if I'm taking the right approach:
I multiplied the first line by 4 and the second line by -2 .... is that right? From then on, I can't seem to come out with a decent answer because something doesn't seem right.
Thanks so much for the help, explaining your steps only HELPS ME! : )
------------------
4x + 10y = 18
.........
I understand how to solve using elimination, but what's throwing me for a loop is the fact that one line has a subtract sign and the second line is an addition sign. I just don't know which one to turn into a negative!
This is what I've been doing, please tell me if I'm taking the right approach:
I multiplied the first line by 4 and the second line by -2 .... is that right? From then on, I can't seem to come out with a decent answer because something doesn't seem right.
Thanks so much for the help, explaining your steps only HELPS ME! : )
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Multiply the first one by 2 then first add them to lose the y's then subtract to lose the x's
4x - 10y = 22
4x + 10y = 18 add
8x = 40
x = 5
4x - 10y = 22
4x + 10y = 18 subtract
- 20y = 4
20y = - 4
y = - 4/20
y = - 1/5
Check
2*5 - 5 * - 1/5 = 10 + 1
Ans correct
x = 5 and y = -1/5
4x - 10y = 22
4x + 10y = 18 add
8x = 40
x = 5
4x - 10y = 22
4x + 10y = 18 subtract
- 20y = 4
20y = - 4
y = - 4/20
y = - 1/5
Check
2*5 - 5 * - 1/5 = 10 + 1
Ans correct
x = 5 and y = -1/5