John’s income is $100 a week, CD is $10 each and price of a book is $20. John’s utility is represented by figure 1 below. (DO NOT assume U=XY)

a. What is the equation for John’s budget line?

b. Graph John’s budget line

Here is my work:

10Qcd + 200b = 100

Qcd + 200b / 10cd * Qqb = Y / 10cd

Qcd = y/10cd - 200b/10cd * Qb

100/10 cd - 200/10 cd * Qb

Qcd = 10 - 20Qb

Where do I go from here to find out the budget equation and the coordinates to graph the budget line?

Thankyou!