Question

draw the graph of the polynomial f(x) = x^2-2x-8

Answer 1

Question:-

draw the graph of the polynomial f(x) = x^2-2x-8

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Given,

f(x)=x² −2x−8

to find the vertex, we know,

x=−b/ 2a = - (-2)/2×1 =1

to find y coordinate, substitute the value of x in equation.

(1)² −2(1)−8=1−2−8=9

The vertex is (1,9)

Now, x intercepts,

x² −2x−8=0

(x−4)(x+2)=0

x=−2,4

The x intercepts are (−2,0),(4,0)

To find the y intercept, substitute x=0 in given equation,

0 ²-2(0)−8=−8

The y intercept is (0,−8)

Thus it is an upward facing parabola, touching x and y axis at (2,−8),(−1,−5),(3,−5)

hope it helps you..

Answer 2

HELLO

Given,

f(x)=x² −2x−8

to find the vertex, we know,

x=−b/ 2a = - (-2)/2×1 =1

to find y coordinate, substitute the value of x in equation.

(1)² −2(1)−8=1−2−8=9

The vertex is (1,9)

Now, x intercepts,

x² −2x−8=0

(x−4)(x+2)=0

x=−2,4

The x intercepts are (−2,0),(4,0)

To find the y intercept, substitute x=0 in given equation,

0 ²-2(0)−8=−8

The y intercept is (0,−8)

Thus it is an upward facing parabola, touching x and y axis at (2,−8),(−1,−5),(3,−5).

HOPE IT HELP U