The equation of a parabola is y=x2+8x+21. Write the equation in vertex form.Write any numbers as integers or simplified proper or improper fractions.______
Q. The equation of a parabola is y=x2+8x+21. Write the equation in vertex form.Write any numbers as integers or simplified proper or improper fractions.______
Identify vertex form: Identify the vertex form of a parabola.The vertex form of a parabola is given by the equation y=a(x−h)2+k, where (h,k) is the vertex of the parabola.
Complete the square:Complete the square to rewrite the given equation in vertex form.We start with the given equation y=x2+8x+21. To complete the square, we need to find the value that makes x2+8x a perfect square trinomial. We do this by taking half of the coefficient of x, squaring it, and adding it to and subtracting it from the equation. The coefficient of x is 8, so half of 8 is 4, and 4 squared is 16. We add and subtract 16 to the equation.
Add and subtract: Add and subtract 16 to the equation.y=x2+8x+16+21−16Now we have the perfect square trinomial x2+8x+16 and the constants 21 and −16.
Factor and simplify: Factor the perfect square trinomial and simplify the constants.y=(x+4)2+21−16y=(x+4)2+5Now the equation is in vertex form, where (h,k)=(−4,5).
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