Question

A.Directions: Solve the system of equations (by elimination)

1.
x + 2y = 7
x - y = 4

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Answer 1

x=5

Explanation:

X+2y=7

X-y=4

2(x-y)= (4)2= 2x-2y= 8

x+2y=7

2x-2y=8

3x=15

15/3=5 X=5

-2y+2y=0

Answer 2

x + 2y = 7.........(1)

x - y = 4 ...........(2)

Explanation:

subtracting equation 2 from 1

x+2y=7

x-y=4

-

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2y--y=7-4

3y=3

y=3/3=1

multiplying equation 2 by 2

2x-2y=8............(3)

adding equation 1 and 3

2x-2y=8

x+2y=7

+

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2x+x=8+7

3x=15

x=15/3=5

:.x=5

:.y=1