Q. y=3(2x2−x−1)y=4x+2If (x1,y1) and (x2,y2) are distinct solutions to the system of equations shown, what is the value of y1+y2 ?
Set Equations Equal: We have the system of equations:y=3(2x2−x−1)y=4x+2To find the solutions (x1,y1) and (x2,y2), we need to set the two equations equal to each other and solve for x.3(2x2−x−1)=4x+2
Distribute and Simplify: Distribute the 3 on the left side of the equation: 6x2−3x−3=4x+2
Quadratic Formula: Move all terms to one side to set the equation to zero:6x2−3x−3−4x−2=06x2−7x−5=0
Substitute Values: Now we need to solve the quadratic equation6x2−7x−5=0. This can be done by factoring, completing the square, or using the quadratic formula. The equation does not factor easily, so we will use the quadratic formula:x=2a−b±b2−4acwhere a=6, b=−7, and c=−5.
Solve for x: Substitute the values of a, b, and c into the quadratic formula:x=2(6)−(−7)±(−7)2−4(6)(−5)x=127±49+120x=127±169x=127±13
Find y Values: Solve for the two possible values of x:x1=127+13=1220=35x2=127−13=12−6=−21
Calculate y1+y2: Now we need to find the corresponding y values for each x by substituting x1 and x2 into either of the original equations. We'll use the simpler equation y=4x+2. For x1=35: y1=4(35)+2y1=320+2y1=320+36y0
Calculate y1+y2: Now we need to find the corresponding y values for each x by substituting x1 and x2 into either of the original equations. We'll use the simpler equation y=4x+2. For x1=35: y1=4(35)+2y1=320+2y1=320+36y0For y1: y2y3y4
Calculate y1+y2: Now we need to find the corresponding y values for each x by substituting x1 and x2 into either of the original equations. We'll use the simpler equation y=4x+2. For x1=35: y1=4(35)+2y1=320+2y1=320+36y0For y1: y2y3y4Now we can find y1+y2: y6y7
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