The equation below describes a proportional relationship between x and y. What is the constant of proportionality? y= 2/5x

Afootball is throw by a quarterback to a receiver

If tan2a=cot(a+60), find the value of a, where 2a is an acute angle

1. 2. ∠b and ∠y are right angles. 3.? 4.? which two statements are missing in steps 3 and 4? ∠x ≅ ∠c △abc ~ △zyx by the sas similarity theorem. ∠b ≅ ∠y △abc ~ △zyx by the sas similarity theorem. = 2 △abc ~ △zyx by the sss similarity theorem. = 2 △abc ~ △zyx by the sss similarity theorem.