Clear till here? Good.
Now we have to take factors twice.
So we get
........[first time]
......[second time]
......[simplified]
Therefore we get our value of 's' as

Now base and side are equal,therefore

So we have our values as

We can verify this using the [A=1/2bh] formula,
Area=1/2*s*h

And thus we know that our values for s and h are correct.
Hope this helps,
Prabhat
Answer by cleomenius(959)   (Show Source): You can put this solution on YOUR website!
We can use the formula for Area of an equilateral triangle to find the side length.
Area = s^2/4
30 = s^2/4
120 = s^2
69.28 = s^2
8.23 cm = s
the altitude h of an equilateral triangle is :
h = side * sin 60 degrees.
8.23 (0.866) = 7.13 cm
To check,
1/2(8.23 * 7.13) = 29.3 Approx 30.