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3 votes
Find a solution to the following system of equations

-5x+2y=9
3x+5y=7

(1, 7)
(–9, 7)
(0, 1)
(–1, 2)

User Domen
by
7.3k points

2 Answers

4 votes
oh sorry to disappoint u i got the answer wrong lol i tried
-5x+2y=9 3x+5y=7
-3x -3x
5y=-3x+7
5 5 5
y=-3/5x + 1.4
so um maybe -1,2
i suck.
User ElMesa
by
8.3k points
5 votes
So the best method is elimination method. This is what you do.

-5x + 2y = 9
3x + 5y = 7
You need to cancel out one variable so lets cancel out the x-value.
Multiply the top equation by 3 and multiply the bottome by 5.
Your new set of equations is.
-15x + 6y = 27
15x +25y = 35
Add both equations.
31y = 62
Divide.
y = 2
Plug in 2 into one of the equations.
3x + 5(2) = 7
3x + 10 = 7
Subtract 10
3x = -3
Divide
x = 1
So your solution is (-1,2) I hope this helps love! :)
User Calmrat
by
9.2k points