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3 years ago

Find the solution of the system of equations . - 5x + 9y = 11 x - 3y = - 7 how do i solve this

Mathematics

1 answer:

DIA [1.3K]3 years ago

3 0

Answer:

Solution: x=5, y=4

Step-by-step explanation:

System of Equations

We need to solve:

- 5x + 9y = 11

x - 3y = - 7

There are several ways to solve a system of linear equations. We'll take advantage of the second equation since it has the x with coefficient 1 and solve it for x:

x = - 7 + 3y

Now replace it into the first equation:

- 5(- 7 + 3y) + 9y = 11

Operate:

35 - 15y + 9y = 11

Simplify:

35 - 6y = 11

Rearrange:

- 6y = 11 - 35 = -24

Solve:

y = -24 / -6

y = 4

Finally, since

x = - 7 + 3y

x = - 7 + 3*4

x = - 7 + 12

x = 5

Solution: x=5, y=4

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