WAEC 2022 · Paper 1 · Q4

If $\sqrt{24} + \sqrt{96} - \sqrt{600} = y\sqrt6$ , find the value of $y$ .

Worked solution (try it first)

Take out square factors: $\sqrt{24} = 2\sqrt6$ , $\sqrt{96} = 4\sqrt6$ and $\sqrt{600} = 10\sqrt6$ .
Combine: $2\sqrt6 + 4\sqrt6 - 10\sqrt6 = -4\sqrt6$ .
So $y = -4$ , option D.