# Simulaneous Non Linear Equation Solver

Description

This is a template that allows the use of the Solver tool in Excel to solve a set of coupled non-linear equations. It makes use of the Solver add-in.

.xls file (18 KB) (This file contains the example described below.)

## How to use

The use of this template is best illustrated by an example. Let us solve the following coupled  simultaneous non-linear equations:

x = sin(y) and y = cos(x)

Initial guesses for the variables are entered under 'Variables' in column A and the equations are keyed into column B. The equations must be in the form f(variables) = 0, hence we key in the equations as:

x - sin(y) and y - cos(x)

The figure below shows the setup.

Now go to Tools, choose Solver and set it up to target cell C4 to 0 as shown in the figure below.

Solver will try to find a solution to the equations. In this case, it comes up with the following solution:

x = 0.6951 radians (39.8 degrees), y = 0.7684 radians (44.0 degrees)

## Also See:

Non-linear Equation Solver

Linear Equation Solver

First order ODE Solver