Question

Sumin bought a pen and a book for $x. the pen cost $5. (a) express the cost of the book in terms of x. (b) if x = 11, find the cost of the book. (c) if x = 15, find the cost of the book.

Answer 1

a. x = total - $5

b. x = $6

c. x = $10

Explanation:

a. pen + book = total

Let x = book

$5 + x = total

x = total - $5

b. pen + book = total

Total = 411

$5 + x = $11

x = $11 - $5

x = $6

c. pen + book = total

Total = $15

$5 + x = $15

x = $15 - $5

x = $10