Write an equation of the line that goes through 10, -6 and is perpendicular to the line 5X plus 7Y equals 21

In the rectangle below ac=30 units what is de

Pls! does anybody know a shortcut for answering these types of questions in the future?

Student price tickets to a movie are $1 and non student tickets are $2. 350 tickets are sold and the total amount made is $450. how many non student tickets were sold ? a) 100 b) 150 c) 200 d)250