Expert: Abe Mantell - 8/13/2009

Question
Problem #1
Find the values of x and y that solve the following system of equations:
-5x – 7y = -14
-6x – 5y = 7

Problem #2
Express the following product of powers of t as a single power of t:
t2 • t5 • t

Problem #3
Simplify the following:
ab5/a2b4

Problem #4
Simplify. Write your answer without parentheses.
(x2/-2y3)2

Problem #5
Rewrite the following without an exponent:
(6/7)-2


Abe thank you for all your help and may God bless you for using your gift for helping someone like me.

Answer
Hello Maria,

1. -5x – 7y = -14 & -6x – 5y = 7...solve by "elimination"...multiply the 1st
equation by -6 and the 2nd by 5 to get: 30x+42y=84 and -30x-25y=35...now add them
to get 17y=119, so y=7...now substitute y=7 into either of the two equations to get x=-7

2. I gather you meant: t^2 • t^5 • t, yes?  If so, then we simply add the exponents:
t^2 • t^5 • t^1 = t^8

3. Did you mean ab^5/(a^2b^4)?

4. Did you mean (x^2/-2y^3)^2?

5. Did you mean (6/7)^(-2)?

TTYL, Abe