Eliminate x: Since the coefficients of x are the same in both equations, we can eliminate x by subtracting the second equation from the first.(–9x−4y)−(–9x−7y)=2−(–10)
Perform Subtraction: Perform the subtraction to eliminate x.−9x+9x−4y+7y=2+10
Simplify Equation: Simplify the equation. 0x+3y=12
Solve for y: Solve for y.3y=12y=312y=4
Substitute and Solve for x: Substitute the value of y back into one of the original equations to solve for x. We can use the first equation.−9x−4(4)=2
Finalize Solution: Simplify the equation and solve for x. –9x−16=2 –9x=2+16 –9x=18 x=(–9)18 x=–2
Finalize Solution: Simplify the equation and solve for x.\begin{align*} -9x - 16 &= 2\ -9x &= 2 + 16\ -9x &= 18\ x &= \frac{18}{(-9)}\ x &= -2 \end{align*}Write the solution as an ordered pair.The solution to the system of equations is (x,y)=(−2,4).
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