How do I solve 10x-x+4y-9x

According to the 2008 u.s. census, california had a population of approximately 4 × 10^7 people and florida had a population of approximately 2 × 10^7 people. which of the following is true? a. the population of florida was approximately two times the population of california. b. the population of florida was approximately twenty times the population of california. c. the population of california was approximately twenty times the population of florida. d. the population of california was approximately two times the population of florida.

Someone me what is the area of this figure? 18m 18m 8m 16m

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