## Monday, May 23, 2016

### Daily Regents: Factoring and Compound Interest

I'll be reviewing a New York State Regents Exam Question every day from now until the Regents exams begin next month. At least, that is the plan.

### August 2014, Questions 25 and 26

25. In the equation x2 + 10x + 24 = (x + a)(x + b), b is an integer. Find algebraically all possible values of b.

x2 + 10x + 24 factors into (x + 4)(x + 6), the order of the two binomials doesn't matter.
So the possible values of b are 4 and 6.

26. Rhonda deposited \$3000 in an account in the Merrick National Bank, earning 4.2% interest, compounded annually. She made no deposits or withdrawals. Write an equation that can be used to find B, her account balance after t years.

The formula you need is B = P(1 + r)t
P = 3000, the principal, or starting amount
r = .042, which is 4.2% as a decimal
t is time. No specific value is given, so use the variable.

That makes the answer B = 3000(1.042)t

Any questions?

If anyone in Brooklyn is looking for an Algebra or Geometry Regents Prep tutor, send me a note. I have a couple of weekly spots available between now and June.