solve application using matrices

Question

Y=C+I
C=100+ 0.9Y
I=200

Answer 1

The equations are Y = C + I

C = 100 + 0.9Y

I = 200

From the equations we can also write Y - C - I = 0 --------> (1)

- 0.9Y + C + 0*I = 100 ---------> (2)

0*Y + 0*C + I = 200 ------------> (3)

Now solve the equations in Cramer's rule

Write the equations into matrices form AX  = B .

A  is coefficient matrix , X  is variable matrix and B  is constant matrix.