Q. Solve the system of equations.−5x+4y=3x=2y−15x=□y=□
Solve for x: Solve the second equation for x.The second equation is x=2y−15. We can use this expression for x to substitute into the first equation.
Substitute x into first equation: Substitute x=2y−15 into the first equation.The first equation is −5x+4y=3. Replace x with 2y−15 to get:−5(2y−15)+4y=3
Distribute and combine like terms: Distribute −5 and combine like terms.−10y+75+4y=3−6y+75=3
Isolate the variable y: Isolate the variable y.Subtract 75 from both sides of the equation to get:−6y=3−75−6y=−72
Solve for y: Solve for y.Divide both sides by −6 to find the value of y:y=−6−72y=12
Substitute y into second equation: Substitute y=12 into the second equation to find x.The second equation is x=2y−15. Substitute y with 12:x=2(12)−15x=24−15x=9
Check the solution: Check the solution in the first equation.Substitute x=9 and y=12 into the first equation −5x+4y=3:−5(9)+4(12)=3−45+48=33=3The left side equals the right side, so the solution checks out.
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