Question 1073271
let x = number of psychology books sold.
let y = number of history books sold.


a total of 368 books were sold.


x + y = 268


the number of history books sold was 58 less than the number of psychology books sold.


y = x - 58


you have 2 equations that need to be solved simultaneously.


they are:


x + y = 268
y = x - 58


since y = x - 58, then replace y in the first equation with x - 58 to get:


x + (x - 58) = 268


remove parentheses to get x + x - 58 = 268.


combine like terms to get 2x - 58 = 268.


add 58 to both sides to get 2x = 326.


divide both sides by 2 to get x = 163.


since x + y = 268, then y = 268 - 163 = 105


the number of psychology books sold is 163.
the number of history books sold is 105.


163 - 105 = 58.


there were 58 less history books sold than psychology books.