Expert: Abe Mantell - 1/8/2008

Question
Hi, I am in high school taking a PreCalc course and am having trouble. My teacher doesn't know how to explain things well. So I hope you can help.

Directions: Find all real solutions to each equation.

(y-1)2-(y-1)=2

after the first (y-1) it is squared.  Please help me!

Tiffany

Answer
Hello Tiffany,

Sorry to hear your math teacher is not good at explaining
things.  :-(

FYI: Common notation for "rasing to a power" is "^"...
---- so (y-1) squared would be written as (y-1)^2.

What you have is (y-1)^2-(y-1)=2
expanding gives: (y^2-2y+1)-y+1=2
simplifying: y^2-3y+2=2, now -2 from both sides:
==> y^2-3y=0...now factor: y(y-3)=0...now the only way
the product of two numbers can be zero, is if at least
one of them is zero...so: either y=0 OR y-3=0 ==> y=3.

Thus, the solutions are y=0 OR y=3.

Let me know if you need any more help!

BTW: WHat grade r u in?  TTYL, Abe