Find the quadratic function that has the vertex (4,5) and passes through the point (8,21) If possible, can you explain the work?
Thanks! *71 POINTS!*
1 answer:
Start by looking at the vertex form of a quadratic function, f(x) = a(x - h)^2 + k. The variables h and k are the values of the vertex. Plug those in to get f(x) = a(x - 4)^2 + 5. To find the variable a, plug in the point given for the x and y values. So, you get (21) = a((8) - 4)^2 + 5. Solve for a algebraically, and you get a = 1. Finally, plug everything in and simplify the equation. You should get that the quadratic function is f(x) = x^2 - 8x + 21. Hope this helps!
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Step-by-step explanation:
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Step-by-step explanation:
Alrighty let's do this.
We know that formula for the Area of a triangle is:
They give us the area as , so let's include it in the equation.
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bring everything to one side so we can make a quadratic and factor:
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