Q. Solve the system by substitution.y=−5xy=−x+4(□,□)
Set Equations Equal: Set the two equations equal to each other since they both equal y.Since y=−5x and y=−x+4, we can set −5x equal to −x+4.
Solve for x: Solve for x.−5x=−x+4Now, add 5x to both sides to get all x terms on one side.−5x+5x=−x+4+5x0=4x+4
Isolate x: Isolate x.Subtract 4 from both sides to solve for x.0−4=4x+4−4−4=4x
Divide to Find x: Divide both sides by 4 to find the value of x.−44=44x−1=x
Substitute for y: Substitute x back into one of the original equations to solve for y. We can use y=−5x. y=−5(−1)y=5
Check Solution: Check the solution with the other equation.Substitute x=−1 into y=−x+4.y=−(−1)+4y=1+4y=5Since this matches the y value we found when we substituted into the first equation, our solution is correct.
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