Gillian purchased 25 books at the library book sale. each hardcover book cost $1.50, and each paperback book cost $0.50. gillian spent a total of $26.50. the book costs can be represented by the system of equations below.

h + p = 25
1.50h + 0.50p = 26.50
how many paperback books did gillian buy?

11
12
13
14
11

A) 11

Step-by-step explanation:

Given:

Gillian purchased 25 books at the library book sale. Each hardcover book cost $1.50, and each paperback book cost $0.50. Gillian spent a total of $26.50. The book costs can be represented by the system of equations below.

h + p = 25   (1)

1.50h + 0.50p = 26.50  (2)

Here we need to solve the system of equations and find the p.

From the equation (1), we can rewrite

h = 25 -p [We solve for p]

Now plug in h = 25 - p in the second equation 1.50h + 0.50p = 26.50

1.50(25 -p) + 0.50p = 26.50

Used the distributive property a(b -c) = ab -ac and expand.

1.50(25) - 1.50p + 0.50p = 26.50

37.50 - 1.50p +0.50p = 26.50

Simplify the like terms.

37.50 - 1p = 26.50

This can be written as

1p = 37.50 - 26.50

p = 11

So the number of paper book Gillian buy is 11.