help me with this please

Question

Answer 1

The supply is linear.

114.86 = a + 44b                      ....... (1)
144.86 = a + 114b                     ....... (2)
Solve equations

a = 96, b = 0.43
The supply function is P= 96 +0.43Qs

P is the price and Qs are number of books supplied.
Price, P= $135,

Qs= (135-96)/0.43

    = 90.7
The lowest price is when Qs=0, P=$96