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3 years ago

Can someone help me please?

Mathematics

1 answer:

Finger [1]3 years ago

5 0

Answer: x = 4

y = - 3

Step-by-step explanation:

The given system of simultaneous equations is expressed as

x-3y = 13 ------------------------1

2x+4y=-4--------------------------2

We would apply the method of substitution in solving the equations. From equation 1, we would make x to stand alone by adding 3y to the left hand side and the right hand side of the equation. It becomes

x - 3y + 3y = 13 + 3y

x = 13 + 3y

Substituting x = 13 + 3y into equation 2, it becomes

2(13 + 3y) + 4y = - 4

26 + 6y + 4y = - 4

26 + 10y = - 4

Subtracting 26 from the left hand side and the right hand side of the equation, it becomes

26 - 26 + 10y = - 4 - 26

10y = - 30

Dividing the left hand side and the right hand side of the equation by 10, it becomes

10y/10 = - 30/10

y = - 3

Substituting y = - 3 into x = 13 + 3y, it becomes

x = 13 + 3 × - 3

x = 13 - 9

x = 4

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