Posted by Crystal on Friday, June 12, 2009 at 5:39pm.
Use substitution to determine whether the ordered pair (–2, –3) is a solution of the equation x^2 – y = 7
I say no, but am still not sure because the signs are confusing. Am I correct? Thanks!

Math  Reiny, Friday, June 12, 2009 at 5:50pm
let's see if the point satisfies the equation
Left Side
= x^2  y
= (2)^2  (3)
= 4 + 3
= 7
Right Side = 7
Mmmmhhh? 
Math  Crystal, Friday, June 12, 2009 at 5:51pm
I guess this makes sense but I got 1 for the answer. Did I confuse the signs?

Math  Ms. Sue, Friday, June 12, 2009 at 6:00pm
Yes. You confused the signs. Perhaps you thought that 2^2 was 4. But when you multiply two negative numbers, the answer must be positive.