Question

If k > 0 and x = 7 in the equation above, what is the

value of k ?
A) 2
B) 3
C) 4.
D)5

Answer 1

k=4 C) is the correct answer.

Explanation:

Plugging in the value,

`\sqrt{2k {}^(2) + 17} - x = 0 \\ \sqrt{2k {}^(2) + 17} - 7 = 0 \\ \sqrt{2k {}^(2) + 17 } = 7 \\ 2k {}^(2) + 17 = 49\\ 2k {}^(2) = 32 \\ k {}^(2) = 16 \\ k = 4`