Question #b0e8c

1 Answer
Aug 1, 2015

You must solve this system of equations by substitution.

Explanation:

This problem looks really bad when you look at it. However, many times in mathematics, things that look bad really are not when you use basic principles.

Here we have a system of equations where the variables are already solved, The Y, C, &, I. This means it is set up perfectly for substitution.

We are going to take the equation:
Y = C + I
and substitute the C for the a+bY and I for the u+vY

here is what that looks like:
Y= (a+bY) + (u+vY)

solve for Y by moving all the Y to one side:
Y = a+bY+u+vY
Y-bY-vY = a+u

factor out the Y and you get:
Y(1-b-v)=a+u

then divide by the (1-b-v):
Y=(a+u)/(1-b-v)

this is the solution for the total value of the economy in terms of just the constants. It really wasn't that hard and that makes us happy!
:)