[tex] \sqrt{5} \times \sqrt{6} + \sqrt{2} \times \sqrt{15} = \\ = \sqrt{5} \sqrt{6} + \sqrt{2} \times \sqrt{15} = \\ = \sqrt{5 \times 6} \times \sqrt{2 \times 15} = \\ = \sqrt{30} + \sqrt{30} = \\ = 2 \sqrt{30} [/tex]