Use elimination to solve the system given below.
17x - 2y = 25
17x + 3y = 5
Question 2...
Use elimination to solve the system of equations given by 3x - 2y = 10 and 5x + 2y = 6.
Thank You All!
2007-02-13 19:19:42 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
For elimination, you need to add a multiple of one equation to another in such a way that takes out one variable entirely. In this case, in the first one, multiply the first equation by -1 and add it to the other.
17x + 3y - 17x + 2y = 5 - 25
When you group, you find the x's disappear, leaving you with
5y = -20.
y = -4.
Plugging that back in, you find that x = 1.
In the second system of equations, you can simply add the equations the way they are.
3x - 2y + 5x + 2y = 10 + 6
8x = 16
x = 2
Plug that back in, and y = -2.
2007-02-13 19:27:33 · answer #1 · answered by Anonymous · 2⤊ 0⤋
Subtract equation 1 from 2...
5y = -20
y = 4
x = 1.
Second question...
Add the two together...
8x = 16
x = 2
y = -2
2007-02-13 23:24:59 · answer #2 · answered by Anonymous · 1⤊ 0⤋
Slight mistatement in the first answer, which otherwise looked good.
You can add a multiple of one equation to a multiple of the other. That's a little more general than what was said, and in many cases is an important distinction.
2007-02-13 19:38:40 · answer #3 · answered by Curt Monash 7 · 0⤊ 1⤋