Python – Solve the Linear Equation of Multiple Variable

Prerequisite: Sympy.solve()

In this article, we will discuss how to solve a linear equation having more than one variable. For example, suppose we have two variables in the equations. Equations are as follows:

x+y =1

x-y =1

When we solve this equation we get x=1, y=0 as one of the solutions. In Python, we use Eq() method to create an equation from the expression. 
 

Syntax : Eq(expression,RHS value)

For example, if we have expression as x+y = 1. It can be written as Eq(x+y,1)

Solving equation with two variables

Construct the equations using Eq() method. To solve the equations pass them as a parameter to the solve() function.

Example : 

Output:

Equation 1:
Eq(x + y, 1)
Equation 2
Eq(x - y, 1)
Values of 2 unknown variable are as follows:
{x: 1, y: 0} 

Solving equation with three variables

Construct the following equations using Eq() and solve then to find the unknown variables.

x +y+z =1

x+y+2z=1

Example:  

Output:

Equation 1:
Eq(x + y + z, 1)
Equation 2
Eq(x - y + 2*z, 1)
Equation 3
Values of 3 unknown variable are as follows:
{x: 0, y: 1/3, z: 2/3}