3x+y=1y=6x2−4x−1If (x,y) is a solution to the system of equations shown, which of the following are x-coordinates of the solutions?Choose 1 answer:(A) −21 and 25(B)−32 and 21(C) 32 and −21(D) 32 and −1}
Q. 3x+y=1y=6x2−4x−1If (x,y) is a solution to the system of equations shown, which of the following are x-coordinates of the solutions?Choose 1 answer:(A) −21 and 25(B)−32 and 21(C) 32 and −21(D) 32 and −1}
Equations Given: We have a system of two equations:1. 3x+y=12. y=6x2−4x−1To solve the system, we can substitute the expression for y from the second equation into the first equation. This will give us an equation with only one variable, x, which we can then solve.
Substitute y into first equation: Substitute y=6x2−4x−1 into the first equation:3x+(6x2−4x−1)=1
Combine and simplify: Combine like terms and simplify the equation:3x+6x2−4x−1=16x2−x−1=1
Quadratic equation: Subtract 1 from both sides to set the equation to zero:6x2−x−2=0
Factor the quadratic: Now we have a quadratic equation. We can solve for x by factoring, completing the square, or using the quadratic formula. The equation looks like it might be factorable, so let's try factoring first.
Set factors to zero: We look for two numbers that multiply to (6)(−2)=−12 and add up to −1. These numbers are −4 and 3. So we can write the equation as: (2x−1)(3x+2)=0
Solve for x: Set each factor equal to zero and solve for x:2x−1=0 or 3x+2=0
Final x-coordinates: Solve the first equation for x:2x=1x=21
Final x-coordinates: Solve the first equation for x:2x=1x=21Solve the second equation for x:3x=−2x=−32
Final x-coordinates: Solve the first equation for x:2x=1x=21Solve the second equation for x:3x=−2x=−32We have found two x-coordinates where the system of equations has solutions: x=21 and x=−32. These correspond to answer choice (B).
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