how to solve this equation ?

You are going to have to use an iterative approach to solve this equation. I don't think you can solve it directly. Excel can do it for you very quickly. Another method would be to do it graphically. If you just need the answer, Excel gives it as 2.091

When I do it as d=(7.6873+0.1183d)^(1/2.808) it converges quickly to 2.090955765.

Cue re-write the equation algebraically as

d=(7.6873+0.1183d)^(1/2.808)

using the law of exponents

start with a d (I started with d=0) and crunch through the equation using this d on the right side of the equal sign to calculate a new d on the left side of the equal sign (the first time I got d= 2.067504772.

Take this calculated value for d and plug into the d on right side of the equation to calculate a new d on the left. This time I got d=2.090695381.

Repeat this operation until the calculated d on the left and the d used on the right are the same to as many decimal places as you want.

Using 8 significant figures (the display on my calculator) I converged on 2.090955765 with 5 iterations.

Excel provides a solver for numeric methods like this---but I'm a little old school.

BTW this is a common method for solving equations where the variables aren't algebraically separable.

Rap

Thanks
Thanks a lot for helping out.

Rushyen