Write the equation of the parabola that passes through the points (2,0), (−1,0), and (3,8). 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 (2,0), (−1,0), and (3,8). 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: Identify the values of p and q from the given points where the parabola crosses the x-axis, which are the points (2,0) and (−1,0). These points give us the x-intercepts of the parabola, so 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 p=2 and q=−1, we get y=a(x−2)(x−(−1)) or y=a(x−2)(x+1).
Find Value of a: Now we need to find the value of a. We can use the third point (3,8) to do this. Substitute x=3 and y=8 into the equation y=a(x−2)(x+1) to solve for a.8=a(3−2)(3+1)
Simplify Equation: Simplify the equation to find the value of a.8=a(1)(4)8=4aa=48a=2
Final Equation: Now that we have found a=2, we can write the final equation of the parabola. Substitute a=2 into the equation y=a(x−2)(x+1).y=2(x−2)(x+1)
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