Q. Solve the system by substitution.y−2x−2y=−7x−2=40
Identify Equations: First, we need to identify the two equations in the system that we will be working with.Equation 1: y=−7x−2Equation 2: −2x−2y=40We will use substitution to solve the system, which means we will substitute the expression for y from Equation 1 into Equation 2.
Substitute y into Equation 2: Substitute y=−7x−2 from Equation 1 into Equation 2.Equation 2 becomes: −2x−2(−7x−2)=40Now we need to simplify and solve for x.
Simplify and Solve for x: Simplify the equation by distributing the −2 into the parentheses.−2x+14x+4=40Combine like terms.12x+4=40
Isolate x Term: Subtract 4 from both sides of the equation to isolate the term with x.12x+4−4=40−412x=36
Solve for x: Divide both sides by 12 to solve for x.1212x=1236x=3
Substitute x into Equation 1: Now that we have the value of x, we can substitute it back into Equation 1 to find the value of y.y=−7(3)−2Calculate the value of y.y=−21−2y=−23
Calculate y: We have found the values of x and y that satisfy both equations in the system.x=3 and y=−23These values are the solution to the system of equations.
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