Please help with this asap

In a two-digit number the units' digit is 7 more than the tens' digit. the number with digits reversed is three times as large as the sum of the original number and the two digits. find the number.

Is a square always, sometimes, or never a parallelogram

Tatiana reads 40 pages of her book every night for x number of nights. write an expression that shows the number of pages she has read