A library is having a book sale to raise money. Hardcover books cost $4 each and paperback books cost $2 each. Lauren spends $26 for 8 books.

4×5

3×2

Step-by-step explanation:

a+b=8 or a=8-b

4a+2b=26

4(8-b)+2b=26

32-4b+2b=26

32-2b=26

32-26=2b

6=2b

b=3

a=8-3

a=5

cut 138 centimeters off

step-by-step explanation:

250-112 = 138

circle area = pi * radius^2

if diameter = 10 then radius = 5

circle area = pi * 5^2

circle area = pi * 25

circle area = 78.5398163397 square units

step-by-step explanation: