Q. Solve the system of equations.9x−4y=−77x−12y=39x=□y=□
Identify Variable to Eliminate: Identify the variable to eliminate. We can choose to eliminate either 'x' or 'y'. In this case, we will eliminate 'y' by finding a common multiple for the coefficients of 'y' in both equations.
Multiply Equations by Common Multiple: Multiply the first equation by 3 and the second equation by 1 to get the coefficients of 'y' to be the same (12).3×(9x−4y)=3×(−7) gives 27x−12y=−21.1×(7x−12y)=1×(39) gives 7x−12y=39.
Subtract Equations to Eliminate Variable: Subtract the second equation from the first to eliminate 'y'.(27x−12y)−(7x−12y)=−21−3927x−7x=−6020x=−60
Solve for x: Solve for 'x'. Divide both sides of the equation by 20 to find the value of 'x'.2020x=20−60x=−3
Substitute x into Original Equation: Substitute x=−3 into the first original equation to solve for 'y'.9(−3)−4y=−7−27−4y=−7
Isolate Term with y: Add 27 to both sides of the equation to isolate the term with 'y'.−4y=−7+27−4y=20
Solve for y: Solve for 'y'. Divide both sides of the equation by −4 to find the value of 'y'.−4−4y=−420y=−5
Write Solution as Coordinate Point: Write the solution as a coordinate point. The solution is (−3,−5).
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