Write the equation of the parabola that passes through the points (−7,−7), (−5,0), and (−2,0). 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 (−7,−7), (−5,0), and (−2,0). 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 (−7,−7), (−5,0), and (−2,0). The points (−5,0) and (−2,0) are the x-intercepts of the parabola, so they correspond to p and q in the equation y=a(x−p)(x−q).
Substitute values into equation: Since the x-intercepts are given by the points where y=0, we can identify p=−5 and q=−2 from the points (−5,0) and (−2,0).
Find value of a: Now we have p=−5 and q=−2. We can substitute these values into the equation to get y=a(x−(−5))(x−(−2)) or y=a(x+5)(x+2).
Substitute third point: Next, we need to find the value of a. We can use the third point (−7,−7) to do this. We substitute x=−7 and y=−7 into the equation y=a(x+5)(x+2) to solve for a.
Solve for a: Substituting the point (−7,−7) into the equation gives us −7=a(−7+5)(−7+2). Simplifying the right side, we get −7=a(−2)(−5).
Write final equation: Now we solve for a: −7=a(10). Dividing both sides by 10 gives us a=−107.
Write final equation: Now we solve for a: −7=a(10). Dividing both sides by 10 gives us a=−107.We have found a=−107. We can now write the final equation of the parabola by substituting a, p, and q into y=a(x−p)(x−q). This gives us y=(−107)(x+5)(x+2).
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