The linear equation that represents all combinations of income $\"\"$ and interest rates $\"\"$ that maintain an equilibrium in the market for goods in the economy.

The system of equations are $\"\"$

Multiply the equation $\"\"$ by $\"\"$ and add to the equation $\"\"$ to eliminate $\"\"$ .

$\"\"$ .

$\"\"$

$\"\"$ .

The rate of interest is $\"\"$ .

Substitute $\"\"$ in equation $\"\"$ .

$\"\"$

$\"\"$ .

Therefore, the equilibrium level of income and interest rates is $\"\"$ million and $\"\"$ .

The equilibrium level of income and interest rates is $\"\"$ million and $\"\"$ .