Write as an algebraic expression: “eleven less than four times the number of text messages"

Two customers went to a post office. first customer paid $12 for 14 and 5 envelopes the second paid 24.80 for 10 postcards and 15 envelopes. what is cost of each envelope?

What is the area of mnp? 40 m2 60 m2 68 m2 127.5 m2

Simplify 15(x - 4)(x -1)-3(x + 4)(x - 1) with steps