Q. Solve the system by substitution.2x+5yx=−2=−4y−4
Identify Equation for Substitution: Identify the equation that can be used for substitution.In the given system of equations, the second equation x=−4y−4 is already solved for x, which makes it a good candidate for substitution.
Substitute x into First Equation: Substitute the expression for x from the second equation into the first equation.Replace x in 2x+5y=−2 with the expression from x=−4y−4.2(−4y−4)+5y=−2
Distribute and Combine Terms: Distribute and combine like terms.2(−4y)−2(4)+5y=−2−8y−8+5y=−2Combine like terms: −8y+5y=−3y−3y−8=−2
Isolate y: Isolate y by adding 8 to both sides of the equation.−3y−8+8=−2+8−3y=6
Solve for y: Solve for y by dividing both sides by -3").\(\newline\$-3y / -3 = 6 / -3\)\(\newline\)\(y = -2\)
Substitute \(y\) into Second Equation: Substitute the value of \(y\) back into the second equation to solve for \(x\).\[x = -4y - 4\]\[x = -4(-2) - 4\]\[x = 8 - 4\]\[x = 4\]
Write Solution as Ordered Pair: Write the solution as an ordered pair \((x, y)\). The solution to the system of equations is \((4, -2)\).
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