Advanced MathEasyUndoing a square root
Advanced Math practice question
If √x = 9, what is the value of x?
Answer: 81
Square both sides: x = 9² = 81.
Common wrong answers
- If you answered 3
- 3 is √9, taking another square root instead of squaring.
- If you answered 18
- 18 is 2 × 9, doubling instead of squaring.
- If you answered 4.5
- 4.5 is 9/2, halving instead of squaring.
More Advanced Math questions
- Easy
If f(x) = 3x − 7, what is the value of f(5)? - Easy
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Which of the following expressions is equivalent to x² + 7x + 12 ? - Easy
The function g is defined by g(x) = x³ + 2x. What is the value of g(−2) ? - Easy
For x > 0, which of the following is equivalent to ∛(x⁵) ? - Easy
The function h is defined by h(x) = (x − 6)(x + 2). What is one value of x for which h(x) = 0 ?
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