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Solve the system 2x-2y=10 4x-5y=17

User Lawzlo
by
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2 Answers

3 votes
multiply 2x-2y=10 by 2,
4x-4y=20,
given:4x-5y=17
y=3
pluck it in
2x-6=10
move the 6 to the right
2x=16
divide
x=8
y=3
User Rchurt
by
7.7k points
4 votes
Equation 1) 2x - 2y = 10
Equation 2) 4x - 5y = 17

Multiply ALL of equation 1 by 2.

1) 2(2x - 2y = 10)

Simplify.

1) 4x - 4y = 20
2) 4x - 5y = 17

Subtract equations from one another.

y = 3

Plug in 3 for y in the first equation.

1) 2x - 2y = 10

2x - 2(3) = 10

Simplify.

2x - 6 = 10

Add 6 to both side.s

2x = 16

Divide both sides by 2.

x = 8

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Check your work by plugging in 8 for x, and 3 for y into the original equations.

2x - 2y = 10 & 4x - 5y = 17

1) 2x - 2y = 10

2(8) - 2(3) = 10

Simplify.

16 - 6 = 10

10 = 10

2) 4x - 5y = 17

4(8) - 5(3) = 17

Simplify.

32 - 15 = 17

17 = 17

Therefore, x = 8, y = 3

~Hope I helped!~
User Enkelejda
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7.5k points