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6 votes
6 votes
Find an equation for a quadratic function that contains the points (1,2) and (5,10)

User Emanuel
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1 Answer

12 votes
12 votes

Answer:

y = x^2 -4x +5

Explanation:

There are an infinite number of such equations. If we choose the leading coefficient to be 1, then we can find the other coefficients from ...

y = x^2 +bx +c

2 = 1^2 +b(1) +c ⇒ b + c = 1

10 = 5^2 +b(5) +c ⇒ 5b +c = -15

Subtracting the first equation from the second gives ...

(5b +c) -(b +c) = (-15) -(1)

4b = -16

b = -4

c = 1 -b = 1 -(-4) = 5

The quadratic function could be ...

y = x^2 -4x +5

User Bearoplane
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2.8k points