Q. A parabola opening up or down has vertex (0,5) and passes through (−10,−20). Write its equation in vertex form.Simplify any fractions.
Equation Simplification: Now we have the equation y=a(x−0)2+5, which simplifies to y=ax2+5. We need to find the value of 'a' using the point (−10,−20) that lies on the parabola.
Substitute and Solve: Substitute x=−10 and y=−20 into the equation to find 'a'.−20=a(−10)2+5−20=100a+5Now, we solve for 'a'.
Isolate 'a': Subtract 5 from both sides of the equation to isolate the term with 'a'.−20−5=100a−25=100aNow, divide both sides by 100 to solve for 'a'.
Find 'a' Value:−10025=a−41=aWe have found the value of 'a' to be −41. Now we can write the equation of the parabola in vertex form.
Write Vertex Form: The equation of the parabola in vertex form is y=a(x−h)2+k. Substituting the values of 'a', 'h', and 'k', we get:y=−41(x−0)2+5This simplifies to y=−41x2+5.
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