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Solve systems by elimination. Solve for the system2x - 4y = 6-5x - 20y = - 15

1 Answer

5 votes

we have the system

2x - 4y = 6 -------> equation A

-5x - 20y = - 15 -----> equation B

Solve by elimination

so

Multiply equation A by -5 both sides

-5*[2x - 4y = 6] -----> -10x+20y=-30 -------> equation C

step 2

Adds equation C and equation B

-10x+20y=-30

-5x - 20y = - 15

------------------------

-15x=-45

x=3

Find out the value of y

substitute the value of x in any equation

2(3) - 4y = 6

6-4y=6

-4y=6-6

-4y=0

y=0

therefore

the solution is (3,0)

User Fernando Madruga
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