Q. Solve the system of equations.7x−3y=20y=5x−4x=□y=□
Substitute y into first equation: Substitute y from the second equation into the first equation.We have y=5x−4. Substitute this into 7x−3y=20.7x−3(5x−4)=20
Distribute and simplify: Distribute the −3 across the parentheses and simplify.7x−15x+12=20−8x+12=20
Isolate the variable : Isolate the variable .\newline−8-8−8x = 888
Solve for x: Solve for x.\newline−8x=8-8x = 8−8x=8\newlinex=8−8x = \frac{8}{-8}x=−88\newlinex=−1x = -1x=−1
Substitute xxx back into second equation: Substitute xxx back into the second equation to solve for yyy. y=5x−4y = 5x - 4y=5x−4 y=5(−1)−4y = 5(-1) - 4y=5(−1)−4 y=−5−4y = -5 - 4y=−5−4 y=−9y = -9y=−9
Write the solution as an ordered pair: Write the solution as an ordered pair.\newlineThe solution is (x,y)=(−1,−9)(x, y) = (-1, -9)(x,y)=(−1,−9).
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