Question

A textbook store sold a combined total of 283 math and sociology books in a week. The number of sociology textbooks sold was 89 less than the number of math textbooks sold. How many textbooks of each type were sold

Answer 1

1) show the clues. Let y be the amount of sociology books and x be math book

x+y=283

y+89=x = y= x-89

2) Substitute the second expression for the first.

x+x-89=283

2x -89 = 283

2x = 372

x = 186

Math book sold: 186

3) Use x to find y

186+ y= 283
Y = 97

Sociology book sold: 97

Double check!

97 + 89 = 186
186 = 186

Sociology book sold: 97

Math book sold: 186