Can someone help me solve for Y=+6=5(x-4)?

Asequence is defined recursively by the formula  f(n  +  1)  =  f(n)  +  3 . the first term of the sequence is  –4. what is the next term in the sequence? –7–117

What is the compound interest in a three-year, $100,000 loan at a 10 percent annual interest rate a) 10.00 b) 21.00 c) 33.10 d) 46.41

How do you use the elimination method for this question? explain, because i really want to understand!