SOLUTION: solve the system for all soulutions usin any suitable method y=3x+2 and x-2y=11

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Question 242759: solve the system for all soulutions usin any suitable method y=3x+2 and x-2y=11
Found 2 solutions by jim_thompson5910, blwinbbbles:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
x-2y=11 Start with the second equation.


x-2%283x%2B2%29=11 Plug in y=3x%2B2


x-6x-4=11 Distribute.


-5x-4=11 Combine like terms on the left side.


-5x=11%2B4 Add 4 to both sides.


-5x=15 Combine like terms on the right side.


x=%2815%29%2F%28-5%29 Divide both sides by -5 to isolate x.


x=-3 Reduce.


y=3x%2B2 Go back to the first equation.


y=3%28-3%29%2B2 Plug in x=-3


y=-9%2B2 Multiply


y=-7 Add


So the solutions are x=-3 and y=-7 giving us the ordered pair (-3,-7)

Answer by blwinbbbles(106) About Me  (Show Source):
You can put this solution on YOUR website!
so let's use the elimination method:
y = 3x + 2
x - 2y =11
Set both equations to y
(1) y = 3x + 2
(2) -2y = -x + 11
lets choose the y to eliminate, when we add the two equations together
so we need to make the y in equation 1 be the exact opposite of the y in equation 2...the best way to achieve this is to multiple equation 1 by the number 2, giving us
(1) 2y = 6x + 4
(2) -2y = -x + 11
then adding the equations we get:
0 = 5x + 15
sbubtract 15 from both sides
-15 = 5x
divide by 5 on both sides
-3 = x
Use one of the original equations..and plug in -3 as x..
y = 3(-3) + 2
y = -9 + 2
y = -7