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How do you solve x2 – 4 = 5 by graphing the related function

User Dubbelj
by
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1 Answer

5 votes

Answer:

see attached

Explanation:

The related function we like to graph is the one that has the solutions as its zeros.

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Subtract 5 from both sides.

x² -9 = 0

This is now in the form ...

f(x) = 0

The related function is then ...

f(x) = x² -9

and its zeros are the solutions to the original equation. The zeros (x-intercepts) of f(x) are x = -3 and x = 3.

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Additional comment

The second attachment shows a graph of the given equation. Essentially, its graph is two points on the number line: x = -3 and x = 3.

How do you solve x2 – 4 = 5 by graphing the related function-example-1
How do you solve x2 – 4 = 5 by graphing the related function-example-2
User Arunbh Yashaswi
by
5.8k points