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I solved for the vertex of the parabola I just need help with the two multiple choice questions belowI don’t know which answers are the correct ones to choose

I solved for the vertex of the parabola I just need help with the two multiple choice-example-1
User Rasikh Mashhadi
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1 Answer

15 votes
15 votes

A parabola that opens vertically has the form:


y=a(x-h)^2+k

If a is positive the parabola opens upwards, if a is negative the parabola opens downwards. If a is greater than 1, this parabola is narrower than the parent function x², if a is less than one this parabola is wider than the parent function.

From our problem, rewritting our function in vertex form, we have:


f(x)=5x^2+10x+9=5(x+1)^2+4

Since the coefficient of the binomial is positive and greater than 1, this parabola opens up and it is narrower than the graph y = x².

User Wili
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