Write the equation of the parabola that passes through the points (−1,12), (−2,0), and (1,0). Write your answer in the form y=a(x−p)(x−q), where a, p, and q are integers, decimals, or simplified fractions.
Q. Write the equation of the parabola that passes through the points (−1,12), (−2,0), and (1,0). Write your answer in the form y=a(x−p)(x−q), where a, p, and q are integers, decimals, or simplified fractions.
Identify x-intercepts: We have the points (−1,12), (−2,0), and (1,0). The points (−2,0) and (1,0) are the x-intercepts of the parabola, so they give us the values of p and q directly. Therefore, p=−2 and q=1.
Write parabola equation: Using the values of p and q, we can write the equation of the parabola in the form y=a(x−p)(x−q). Substituting −2 for p and 1 for q, we get y=a(x+2)(x−1).
Find value of a: Now we need to find the value of a. We can use the point (−1,12) to do this. Substituting −1 for x and 12 for y in the equation y=a(x+2)(x−1), we get 12=a(−1+2)(−1−1).
Solve for a: Solving the equation 12=a(1)(−2), we find that 12=−2a, which means a=−6.
Final equation of parabola: Now that we have found a=−6, we can write the final equation of the parabola. Substituting −6 for a, −2 for p, and 1 for q in the equation y=a(x−p)(x−q), we get y=−6(x+2)(x−1).
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