Question:
If \( x^2 - 9 = 16 \), what are the values of \( x \)?
If \( x^2 - 9 = 16 \), what are the values of \( x \)?
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When solving equations like \( x^2 = a \), remember to account for both the positive and negative square roots.
Updated On: Oct 6, 2025
- \( \pm 5 \)
- \( \pm 7 \)
- \( \pm 6 \)
- \( \pm 4 \)
- \( \pm 3 \)
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The Correct Option is A
Solution and Explanation
The given equation is:
\[
x^2 - 9 = 16.
\]
First, add 9 to both sides of the equation to isolate \( x^2 \):
\[
x^2 = 16 + 9 = 25.
\]
Next, take the square root of both sides to solve for \( x \):
\[
x = \pm \sqrt{25} = \pm 5.
\]
Thus, the two possible solutions for \( x \) are:
\[
x = 5
\text{or}
x = -5. \]
\text{or}
x = -5. \]
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