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If x^2 = 81 and x > 0, what is the value of x?

Answer: 9. 1) Take positive root of 81. 2) \sqrt{81} = 9.

Step-by-step solution

1) Take positive root of 81. 2) \sqrt{81} = 9.

Common mistake

Giving -9 too (but x > 0 rules it out).

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What is the answer to If x^2 = 81 and x > 0, what is the value of x?

Answer: 9. 1) Take positive root of 81. 2) \sqrt{81} = 9.

How do you solve it?

1) Take positive root of 81. 2) \sqrt{81} = 9.

What mistake do most students make?

Giving -9 too (but x > 0 rules it out).

What SAT topic is this?

Advanced Math. Practice more free Advanced Math questions with instant feedback at Syntene Learn.

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