Question

I need to find the value of x

Answer 1

Answer: the answer is the square root of 21.

Explanation:

What I did was I just multiplied 7 times 3 and got 21 and that was the answer.

Answer 2

x =
`√(21)`

Explanation:

AC² = AB² + BC²

BC² = 3² + x² = 9 + x²

AB² = 7² + x² = 49 + x²

But AC² = (7 + 3)² = 100

∴ 100 = 49 + x² + 9 + x²

2x² + 58 = 100

x² = 50 - 29 = 21

x =
`√(21)`