Q. Solve the system of equations. −8y+9x=−5 and 8y+7x=−75
Combine equations: Add the two equations to eliminate the variable y. −8y+9x=−5 8y+7x=−75 (−8y+9x)+(8y+7x)=−5+(−75)
Eliminate variable y: Perform the addition to eliminate y. −8y+8y+9x+7x=−5−75 0y+16x=−80 16x=−80
Solve for x: Solve for x by dividing both sides of the equation by 16.1616x=16−80x=−5
Substitute x into equation: Substitute x=−5 into one of the original equations to solve for y. We'll use the first equation −8y+9x=−5. −8y+9(−5)=−5 −8y−45=−5
Isolate term with y: Add 45 to both sides of the equation to isolate the term with y.−8y−45+45=−5+45−8y=40
Solve for y: Solve for y by dividing both sides of the equation by -8").\(\newline\$-8y / -8 = 40 / -8\)\(\newline\)\(y = -5\)
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