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Quadratic: y = -x² - 4x - 1 Step 3: What is the axis of symmetry? y = 3 y = -2 x = -2 x = 3

User Wyman
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1 Answer

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Quadratic: y = -x² - 4x - 1

Step 3: What is the axis of symmetry?

y = 3



y = -2



x = -2



x = 3​

we have the quadratic function


y=-x^2-4x-1

this is represent a vertical parabola open downward

the vertex represent a maximum

the axis of symmetry is thex-coordinate of the vertex

so

Convert the function in vertex form

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

where (h,k) is the vertex

y=h -------> axis of symmetry

therefore

Complete the square

factor -1

y=-(x^2+4x)-1

y=-(x^2+4x+4)-1+4

y=-(x+2)^2+3

the vertex is the point (-2,3)

axis of symmetry is

y=-2

User Compski
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