Question 180513: 5x-y=-18
4x+2y=92
These are both the same problem.I don't get how to do these problems.Could you explain to me how to do this type of problem please?
Found 2 solutions by Alan3354, josmiceli:
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! 5x-y=-18
4x+2y=92
These are both the same problem.
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I think it's one problem, and you want to solve for x and y.
There are 2 equations and 2 unknowns, so it might work out.
One method it elimination. Multiply one of the eqns by something to get the same coefficients for one of the unknowns.
If the 1st eqn is multiplied by 2, it will have -2y in it, and the 2nd eqn has 2y also.
5x-y=-18 --> 10x - 2y = -36
10x - 2y = -36
4x + 2y = 92 Then add the 2 eqns
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14x + 0y = 56
x = 4 xxxxxxxxxxxxxxxxxx That's one
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Then sub 4 for x into an eqn to find y
4x+2y=92
16+2y=92
2y = 76
y = 38 yyyyyyyyyyyyyyyyyyy
That's it.
Answer by josmiceli(19441)  (Show Source):
You can put this solution on YOUR website! What they are is 2 equations with 2
unknowns, so I can assume you are to
solve for  and 
(1) 
(2) 
They should be solvable. If I graph them,
they are 2 intersecting straight lines
and the solution, (x,y) is where they
intersect. I'll graph them
Looking at the graph, the intersection is at about  ,
 , so the solution would be (4,38)
Now I'll find the actual solution
(1)
(2)
Multiply both sides of (1) by  and add the equations
(1) 
(2)
Now put this value of back into (1)
(1)
So, I guessed right. The solution is
(4,38), or in other words,
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