3x + 3y = 0
y = 4x – 10
2006-10-02 11:36:45 · 9 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
3x + 3y = 0 - - - - - - - Equation 1
y = 4x - 10 - - - - - - - - Equation 2
Substitute y = 4x - 10 Into equation 1
3x + 3y + 0
3x + 3(4x - 10) = 0
3x + 12x - 30 = 0
15x - 30 = 0
15x - 30 + 30 = 0 + 30
15x = 30
15x/15 = 30/15
x = 2
The answer is x = 2
The solution set is { 2 }
Insert the x value into equation 2
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Solving for y
y = 4x - 10
y = 4(2) - 10
y = 8 - 10
y = -2
The answer is y = - 2
The solution set is { - 2 }
Insert the y value into the equation 1
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Check for equation 1
3x + 3y = 0
3(2) + 3(- 2) = 0
6 + ( - 6) = 0
6 - 6 = 0
0 = 0
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Check for equation 2
y = 4x - 10
-2 = 4(2) - 10
- 2 = 8 - 10
- 2 = - 2
The solution set { 2, - 2 }
2006-10-02 12:22:24 · answer #1 · answered by SAMUEL D 7 · 0⤊ 0⤋
3x+3(4x-10)=0 solve for x then do the bottom equation by plugging in x where it goes to figure out y
2006-10-02 18:40:17 · answer #2 · answered by < nick > 1 · 0⤊ 0⤋
3x + 3y=0
y= 4x- 10
3x + 3 (4x-10)=10
3x + 12x - 30 =0
15x - 30=0
+30 +30
15x= 30
15 15
x= 2
then:
y= 4x -10
y= 4 (2) - 10
y= 8-10
y=-2
2006-10-02 19:02:21 · answer #3 · answered by amanda 1 · 0⤊ 0⤋
3x + 3y = 0
3x + 3(4x - 10) = 0
3x + 12x - 30 = 0
15x = 30
x = 2
y = -2
2006-10-02 18:38:49 · answer #4 · answered by another newbie 2 · 1⤊ 0⤋
3x+3y=0
y is equal to 4x-10
3x+3(4x-10)=0
(distribute the 3)
3x+12x-30=0
(combine like terms)
15x-30=0
(add 30)
15x-30=0
+30=+30
--------------
15x=30
(divide)
x=2
2006-10-02 18:42:08 · answer #5 · answered by Julie 2 · 0⤊ 0⤋
just substite the y in the top equation...and solve
3x+3(4x-10)=0
3x+12x-30=0
15x-30=0
15x=30
x=2
y=-2
2006-10-02 18:41:48 · answer #6 · answered by kimmykay 3 · 1⤊ 0⤋
3x+3(4x-10)=0
3x+12x-30=0
15x=30
x=2
y=4(2)-10
y=8-10
y=(-2)
2006-10-02 19:10:13 · answer #7 · answered by Yankfan580 2 · 0⤊ 0⤋
3x+3(4x-10)=0
15x-30=0
15x=30
x=2
y=4*(2)-10
y=8-10
y=-2
2006-10-02 18:40:31 · answer #8 · answered by dragonfly140 3 · 1⤊ 0⤋
I am not really adding anything to the argument, but to get full marks:
x = 2
y = -2
2006-10-02 18:40:29 · answer #9 · answered by lx470_98 1 · 0⤊ 0⤋