What is the indicated function value of f(a)

Me find the missing dimension of a triangle height: 7 in., area: 21^2

If a || b and b | y, then ? a) x || y. b) x | a. c) a | y. d) a || y.

Players on the school soccer team are selling candles to raise money for an upcoming trip. each player has 24 candles to sell. if a player sells 4 candles a profit of$30 is made. if he sells 12 candles a profit of $70 is made. determine an equation to model his situation?