Write the equation of the parabola that passes through the points (−1,0), (2,0), and (1,5). 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 (−1,0), (2,0), and (1,5). 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 (−1,0), (2,0), and (1,5). The points where the parabola crosses the x-axis, (−1,0) and (2,0), give us the values of p and q directly, since these are the x-intercepts of the parabola.p=−1 and q=2.
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 −1 for p and 2 for q, we get: y=a(x+1)(x−2).
Find value of a: Now we need to find the value of a. We will use the third point (1,5) for this. Substituting x=1 and y=5 into the equation y=a(x+1)(x−2) gives us:5=a(1+1)(1−2).
Solve for a: Solving the equation 5=a(2)(−1) to find the value of a:5=−2aa=−25.
Final equation: Now that we have found a=−25, we can write the final equation of the parabola.Substituting −25 for a, −1 for p, and 2 for q into the equation y=a(x−p)(x−q), we get:y=−25(x+1)(x−2).
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