GIVING BRAINLIST TO ANYONE WHO SOLVES ANY QUESTION <3

How do i put 3(x+7) in distributive property

Aaron invested a total of $4,100, some in an account earning 8% simple interest, and the rest in an account earning 5% simple interest. how much did he invest in each account if after one year he earned $211 in interest? select one: a. $200 at 8%, $3,900 at 5% b. $3,200 at 8%, $900 at 5% c. $900 at 8%, $3,200 at 5% d. $3,900 at 8%, $200 at 5%

Given: m zade = 60° and m2cdf = (3x + 15) prove: x = 15