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2x+3y=-9-7x+2y=-21x=?y=?The assigments called solving linear systems by elimination but I keep getting stuck on it.. do you know how to do it?

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You have the following system of equations:

2x + 3y = -9

-7x + 2y = -21

In order to solve the previous system of equations, proceed as follow:

- multiply the first equation by -2 and multiply the second equation by 3:

(2x + 3y = -9)(-2)

-4x - 6y = 18

(-7x + 2y = -21)(3)

-21x + 6y = -63

- next, sum the previous equations:

-4x - 6y = 18

-21x + 6y = -63

-25x + 0 = -45

- solve the previous equation for x:

-25x = -45

x = -45/(-25)

x = 9/5

- now, replace the previous values of x into the first equation of the system and solve for y:

2(9/5) + 3y = -9

18/5 + 3y = -9

3y = -9 - 18/5

3y = -45/5 - 18/5

3y = -63/5

y = -21/5

Hence, the solution to the given system is:

x = 9/5

y = -21/5

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