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Find the slope of the function's graph at the given point. Then find an equation for the line tangent to the graph there.

f(x)=x²-7, (-4,9)

1 Answer

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Answer:

the equation of the tangent line to the graph of f(x) at the point (-4, 9) is y = -8x - 23.

Explanation:

To find the slope of the function's graph at the point (-4, 9), you can calculate the derivative of the function f(x) = x² - 7. The derivative will give you the slope of the tangent line at any point on the graph.

f(x) = x² - 7

Now, find the derivative of f(x):

f'(x) = 2x

Now, let's find the slope at the point (-4, 9):

f'(-4) = 2 * (-4) = -8

So, the slope of the graph at the point (-4, 9) is -8.

Now, you can use the point-slope form of a line to find the equation of the tangent line. The point-slope form is:

y - y₁ = m(x - x₁),

where (x₁, y₁) is the point (-4, 9) and m is the slope (-8):

y - 9 = -8(x - (-4))

y - 9 = -8(x + 4)

Now, you can simplify this to the slope-intercept form (y = mx + b):

y - 9 = -8x - 32

Add 9 to both sides:

y = -8x - 32 + 9

y = -8x - 23

So, the equation of the tangent line to the graph of f(x) at the point (-4, 9) is y = -8x - 23.

User Wilfried
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