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21x - 11y = -9 -14x + 8y =4

User Cguenther
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1 Answer

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Answer:

To solve the system of equations:

21x - 11y = -9 (Equation 1)

-14x + 8y = 4 (Equation 2)

We can use the method of elimination or substitution. Let's use the method of elimination:

1. Multiply Equation 1 by 8 and Equation 2 by 11 to make the coefficients of y in both equations opposites:

Equation 1: 168x - 88y = -72 (Equation 3)

Equation 2: -154x + 88y = 44 (Equation 4)

2. Add Equation 3 and Equation 4 to eliminate y:

(168x - 88y) + (-154x + 88y) = -72 + 44

168x - 154x - 88y + 88y = -28

14x = -28

3. Solve for x:

Divide both sides by 14:

x = -28/14

x = -2

4. Substitute the value of x back into either Equation 1 or Equation 2 to solve for y. Let's use Equation 1:

21(-2) - 11y = -9

-42 - 11y = -9

-11y = -9 + 42

-11y = 33

5. Solve for y:

Divide both sides by -11:

y = 33/-11

y = -3

Therefore, the solution to the system of equations is x = -2 and y = -3.

In summary, the solution to the system of equations is x = -2 and y = -3.

Explanation:

User Fortepianissimo
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