Question

$(7sqrt{2}-sqrt{19} ) * (sqrt{19} +7sqrt{2})$

Answer 1

$(7 sqrt{2} - sqrt{19} ) times ( sqrt{19} + 7 sqrt{2}) = (7 sqrt{2} - sqrt{19} times (7 sqrt{2} + sqrt{19} ) = 49 times 2 - 19 = 98 - 19 = 79$