stretchad wrote:

Sorry about that.

I think this one is a fairly simple one, but i feel like there must be an easy rule to remember as problems get increasingly difficult...

If y = 4 + (x - 3)^2, then y is lowest when x =

a - 14

b - 13

c - 0

d - 3

e - 4

the rule is to spread the condensed expression into the form of a quadratic expression IN CASE it's originally in condensed form

For example: y=ax^2+bx+c . This is a parabola. The biggest/ smallest of y then is the peak/ nadir of the parabola. The formula for this point is :

-( b^2-4ac)/ (-4a) ( if i remember correctly, i'll double-check it)

1) if the expression contains -x^2, the question asks for the peak/ the biggest value.

2) if the expression contains x^2, the question asks for the nadir/ the smallest value.

For example: y=x^2 - 6x + 12

the nadir is -[((-6)^2- 4*12*1)/ 4*1] = 3 --> the smallest value of y is 3

OR you can solve it another way by trying to group the expression into froms of

- (ax+b)^2 +c OR (ax+b)^2 +c

For example: x^2-6x+12= (x-3)^2+3