SOLUTION: y=2x-6 y=5x+15

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Question 261618: y=2x-6
y=5x+15
Found 2 solutions by jojo14344, butterfliiizzz:
Answer by jojo14344(1513) About Me  (Show Source):
You can put this solution on YOUR website!


Given:system%28red%28EQN1%29y=2x-6%29%29,system%28red%28EQN2%29y=5x%2B15%29%29

In red%28EQN1%29}, let Fx=0:
y=2%280%29-6=-6
Point (0,-6)

Let Fy=0:
0=2x-6 ---> 2x=6 ---> cross%282%29x%2Fcross%282%29=cross%286%293%2Fcross%282%29
x=3
Point (3,0)


In red%28EQN2%29, let Fx=0:
y=5%280%29%2B15=15
Point (0,15)

Let Fy=0: 0=5x%2B15 ---> 5x=-15 ---> cross%285%29x%2Fcross%285%29=cross%28-15%293%2Fcross%285%29
x=-3
Point (-3,0)


Lines intersect at: : Point (-7,-20)

Thank you,
Jojo

Answer by butterfliiizzz(18) About Me  (Show Source):
You can put this solution on YOUR website!
For this problem, it is telling you the value of y. So simply plug that in where the y is and then solve for x.
2x - 6 = 5x + 15 So what I would do is subtract 5x from each side to get:
-3x - 6 = 15 Now we can add six to both sides, to get rid of the negative 6.
-3x = 21 Now, to get x by itself, we need to divide each side by -3.
-3/-3 =1 We want 1x (or simply, x) on the left. On the right, 21/-3 = -7
So x = -7