Write the equation of the parabola that passes through the points (−4,0), (3,0), and (−1,−6). 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 (−4,0), (3,0), and (−1,−6). Write your answer in the form y=a(x−p)(x−q), where a, p, and q are integers, decimals, or simplified fractions.
Identify Points: We have the points (−4,0), (3,0), and (−1,−6). The points where the parabola crosses the x-axis, (−4,0) and (3,0), give us the values of p and q directly. Therefore, p=−4 and q=3.
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 −4 for p and 3 for q, we get y=a(x+4)(x−3).
Find Value of a: Now we need to find the value of a. We will use the third point (−1,−6) to do this. Substituting x=−1 and y=−6 into the equation y=a(x+4)(x−3), we get −6=a(−1+4)(−1−3).
Solve for a: Solving the equation −6=a(3)(−4), we find that −6=−12a. Dividing both sides by −12, we get a=−12−6=21.
Final Equation: Now that we have found a=21, we can write the final equation of the parabola. Substituting 21 for a, −4 for p, and 3 for q into the equation y=a(x−p)(x−q), we get y=(21)(x+4)(x−3).
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