Question 632645
<pre>
3 + {{{sqrt(3a+3)}}} = 9

Isolate the term with a radical by subtracting 3 from both sides:

    {{{sqrt(3a+3)}}} = 6

Square both sides. Remember that squaring a square root 
takes away both the radical and the 2 exponent: 

 [{{{sqrt(3a+3)}}}}² = 6²
       3a + 3 = 36
           3a = 33
            a = 11

To check, substitute 11 for a in the original:

3 + {{{sqrt(3a+3)}}} = 9
3 + {{{sqrt(3(11)+3)}}} = 9
3 + {{{sqrt(33+3)}}} = 9
3 + {{{sqrt(36)}}} = 9
3 + 6 = 9
    9 = 9

Edwin</pre>