If the prices and the income are doubled, then the budget line will remain unchanged.
M1 = Rs. 20, M2 = Rs. 40
P1 = Rs. 4, P1 = Rs. 8
P2 = Rs 5, P2= Rs. 10
Horizontal intercept =M2/P1 = 40/8 = 5
Vertical intercept =M2/P2 = 40/10 = 4
Slope =-P1/P2 = -8/10 = -0.8
Hence, the vertical intercept, the horizontal intercept and the slope of the budget line will remain the same. The new budget line will be the same as the old budget line but associated with higher income and higher prices of both the goods.
