Solving PDE using Center difference method

I need to calculate the temperature distribution along a 2D plate using the Center Difference Method. The information I got:

d^2T/dx^2 + d^2T/dy^2 = 0

**Boundary Contidions along North edge: 18 degrees

**Boundary Conditions along the West edge: 64 degrees.

**Boundary Conditions along the East edge: 26 degrees.

**Boundary Condition along South edge: 6 degrees.

**Initial Domain Condition = 0 degrees.

**Step size in x direction = 0.05m

**Step size in y direction = 0.05m

Can someone help me out here please?