For this case we have an equation in which we must apply operations to rewrite it in an equivalent way. We must start by raising both sides of the equation to the square. Thus, we eliminate the square root of the left side of equality and finally solve the binomial of the right side of equality.

So we have:

$\sqrt {x ^ 2 + 81} = x + 10\\(\sqrt {x ^ 2 + 81}) ^ 2 = (x + 10) ^ 2\\x ^ 2 + 81 = (x + 10) ^ 2$

By definition: $(a + b) ^ 2 = a ^ 2 + 2ab + b ^ 2$

$x ^ 2 + 81 = x ^ 2 + 2 (x) (10) + (10) ^ 2\\x ^ 2 + 81 = x ^ 2 + 20x +100$

Thus, $x ^ 2 + 81 = x ^ 2 + 20x +100$ is equivalent to $\sqrt {x ^ 2 + 81} = x + 10$

Answer:

$x ^ 2 + 81 = x ^ 2 + 20x +100$

Option D

4 0

3 years ago

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In a function, y varies inversely with x. The constant of variation is 4. Which table could represent the function?

Colt1911 [192]

I don't see a table but I can give you the means to answer it yourself. The inverse function is represented by this: $y= \frac{k}{x}$ where k is your constant. You are given a k value of 4. If you solve this for k then you will get xy=4. In your tables, multiply your x value by your y value within your coordinate points and if you get a product of 4 each time you multiply x by y, then that table is your answer.

8 0

3 years ago

3. Marcus had an average score of 90% on two biology tests about protists. If his first test score was 96%, which score did he r

Maurinko [17]

Answer:

B: 84%

Step-by-step explanation:

7 0

2 years ago