Simplify the expression.

18a + 12x − 12a + 15x

A) 6a + 27x
B) 6a − 3x
C) 30a − 18x
D) −30 −3x

What are the measures of ∠a, ∠b, ∠c and ∠d? explain how to find each of the angles. measure need asap

Sam opened a money-market account that pays 3% simple interest. he started the account with $7,000 and made no further deposits. when he closed the account, he had earned $420 in interest. how long did he keep his account open?

Which of the following is an irrational number