Find the value of x in the triangle shown below.(not a test just need help with khan academy)

Ab and bc form a right angle at point b. if a= (-3,-1) and b= (4,4) what is the equation of bc?

Complete the input-output table for the linear function y = 3x. complete the input-output table for the linear function y = 3x. a = b = c =

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.