Question

Adrian solved the equation ( x² + 9 = 16 ). Identify the mistake, if any.

a) He should have subtracted 9 in Line 2.
b) He did not make a mistake. His answer is correct.
c) He should have added 3 in Line 3.
d) He subtracted incorrectly in Line 4.

Answer 1

Adrian's mistake in the equation ( x² + 9 = 16 ) is that he should have added 3 in Line 3.

Step-by-step explanation:

The mistake in Adrian's solution is that he should have added 3 in Line 3. Let's go through the steps of solving the equation to see where the mistake occurred:

• Step 1: x² + 9 = 16
• Step 2: x² = 16 - 9 = 7
• Step 3: x = √7 + 3 (missing the +3)
• Step 4: x = √7 + 3

So, the correct solution is x = √7 + 3.