SOLUTION: Solve by elimination method 3x-5y=-19 5x+3y=25

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Question 993648: Solve by elimination method
3x-5y=-19
5x+3y=25
Found 2 solutions by Cromlix, Theo:
Answer by Cromlix(4381) About Me  (Show Source):
You can put this solution on YOUR website!
Hi there,
3x-5y=-19.....(1)
5x+3y=25......(2)
Multiply (1) by 3 and (2) by 5
9x - 15y = -57.....(1)
25x + 15y = 125....(2)
Add (1) and (2)
34x.......= 68
x .......= 2
Substitute x = 2 into Equation(1)
3x - 5y = -19
3(2) - 5y = -19
6 - 5y = -19
-5y ...= -25
y......= 5
]x = 2, y = 5]
Hope this helps :-)

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
3x-5y=-19
5x+3y=25

multiply the first equation by 5 and the second equation by 3.

3x - 5y = -19 becomes 15x - 25y = -95

5x + 3y = 25 becomes 15x + 9y = 75

your equations are now:

15x - 25y = -95
15x + 9y = 75

subtract the first equation from the second equation to get:

34y = 170

divide both sides of this equation by 34 to get:

y = 5

go back to either one of your original equations and replace y with 5 and then solve for x.

your original equations are:

3x-5y=-19
5x+3y=25

take the first equation and replace y with 5.

the equation becomes:

3x - 5*5 = -19

simplify to get:

3x - 25 = -19

add 25 to both sides of the equation to get:

3x = 6

divide both sides of the equation by 2 to get:

x = 2

go back to your second original equation of 5x+3y=25 and replace x with 2 and replace y with 5 to get:

5x + 3y = 25 becomes 5*2 + 3*5 = 25 which becomes 10 + 15 = 25 which becomes 25 = 25.

this confirms the solution is correct.