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3 years ago

If (9x − 4)(9x + 4) = ax² − b, what is the value of a? (5 points)

Mathematics

2 answers:

lions [1.4K]3 years ago

8 0

Given, (9x - 4)(9x + 4) = ax² - b

From algebraic identities:

We know, (a + b)(a - b) = a² - b²

Now, 81x² + 36x - 36x - 16 = ax² - b

81x² - 16 = axis² - b

So ax² = 81x²

a = 81

-b = -16

b = 16

Solution

Therefore, the value of a is 81.

<h2>MyHeritage</h2>

Anna35 [415]3 years ago

4 0

Answer:

The value of a is 81

Step-by-step explanation:

The solution is in the image

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Step-by-step explanation:

Given the statement: An observer on top of a 50-foot tall lighthouse sees a boat at a 7° angle of depression.

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In triangle CAB:

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Using tangent ratio:

$\tan (\theta) = \frac{Opposite side}{Adjacent Base}$

$\tan (\angle CAB) = \frac{BC}{AB}$

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Step-by-step explanation:

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