First of all, you have a denominator in the first term. We have to take both terms to common denominator.
LCM (1;2) = 2
[tex] \frac{ \sqrt{m+3} }{2} = \frac{10}{2} [/tex]
Multiply both fractions for 2 to delete the denominator
√m+3 = 10
Since m+3 is under radical, to delete the radical square √m+3 and 10
m+3 = 100
Move known term (3) to the right of equal with changed sign
m = 100-3
m = 97
