I cant understand this I need help. Some example problems are: 3x+4y=22
x-5y=-37
And
-5y=-2x-19
3x=-2y
And -y=-2x-1
4x=2y-2
how do I solve systems by elimination?
2015-04-22 6:29 pm
回答 (2)
2015-04-22 6:50 pm
THREE questions so let us refer to them as 1. , 2.. and 3.
1.
3x + 4y = 22
-3x + 15y = 111________ADD
19y = 133
y = 7
3x + 28 = 22
3x = - 6
x = - 2
x = - 2 , y = 7
2.
2x - 5y = - 19
3x + 2y = 0
4x - 10y = - 38
15x + 10y = 0________ADD
19x = - 38
x = - 2
10y = 30
y = 3
x = - 2 , y = 3
3.
Equations are identical
1.
3x + 4y = 22
-3x + 15y = 111________ADD
19y = 133
y = 7
3x + 28 = 22
3x = - 6
x = - 2
x = - 2 , y = 7
2.
2x - 5y = - 19
3x + 2y = 0
4x - 10y = - 38
15x + 10y = 0________ADD
19x = - 38
x = - 2
10y = 30
y = 3
x = - 2 , y = 3
3.
Equations are identical
2015-04-22 6:48 pm
1).
3x + 4y = 22
x - 5y = -37
19x = 110 - 148
x = -2
y = 7
2).
-5y = -2x - 19
3x = -2y
2x - 5y = -19
3x + 2y = 0
19x = -38
x = -2
y = 3
3).
-y = -2x- 1
4x = 2y - 2
2x - y = -1
4x - 2y = -2
Both equations are the same.
3x + 4y = 22
x - 5y = -37
19x = 110 - 148
x = -2
y = 7
2).
-5y = -2x - 19
3x = -2y
2x - 5y = -19
3x + 2y = 0
19x = -38
x = -2
y = 3
3).
-y = -2x- 1
4x = 2y - 2
2x - y = -1
4x - 2y = -2
Both equations are the same.
收錄日期: 2021-04-21 22:05:45
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