Lydia read 1/5 of her book last week. this week she read 3 times as much as she read last week. write an expression to show how much of her book Lilla has left to read. then simplify the expression.

X is a variable, while parenthesis suggest multiplication. Y equals the amount of her book left.

(1/5) + 3 (1/5) + x = 1

(1/5) + (3/5) + y = 1

Combine like terms

(4/5) + x = 1

Subtract four-fifths

x = (1/5)

Lydia has 1/5 of her book left to read.