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Mariana [72]
2 years ago
5

Solve each system of equations by substitution X + 3y = 6 -x + y = -7

Mathematics
1 answer:
notka56 [123]2 years ago
4 0

Answer:

x = 6.75

y = -0.25

Step-by-step explanation:

Given :

x + 3y = 6 ..................... equation 1

-x + y = -7 ................... equation 2

solving the system of equation by substitution method , from equation 1 , make x the subject of the formula , that is

x = 6 - 3y ........................... equation 3

substitute equation 3 into equation 2 , that is

- ( 6 - 3y) + y = -7

-6 + 3y + y = - 7

-6 + 4y = -7

4y = -7 + 6

4y = -1

y = \frac{-1}{4} = -0.25

substitute  y = \frac{-1}{4} into equation 3 to find the value of x , that is

x = 6 - 3 (\frac{-1}{4})

x = 6 + \frac{3}{4}

x = \frac{27}{4}

x = 6. 75

Therefore :

x = 6. 75

y = - 0.25

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