Equation of a quadratic function from graph

[syncmaster913n]

So there's this question in this workbook I'm going through, as seen in the picture above. (The solution is the bolded part.)

Shouldn't the value for k = -5 instead of 5? What I mean is, the graph is written in the forum y + a(x-h)^2 + k, so the actual vertex form should be:

y = -a(x-h)^2 - k

Shouldn't therefore k in the form written in the question be equal to -5 so that it actually becomes the positive 5 we are after once the equation is switched into proper vertex form?

Please let me know what I'm missing, thank you.

 

[Deleted member 4993]

So there's this question in this workbook I'm going through, as seen in the picture above. (The solution is the bolded part.)

Shouldn't the value for k = -5 instead of 5? What I mean is, the graph is written in the forum y + a(x-h)^2 + k, so the actual vertex form should be:

y = -a(x-h)^2 - k

Shouldn't therefore k in the form written in the question be equal to -5 so that it actually becomes the positive 5 we are after once the equation is switched into proper vertex form?

Please let me know what I'm missing, thank you.

The question is either quoted incorrectly - or it is incorrect.

"y + a(x-h)^2 + k" is not an equation, because it does have an "equal to" (=) sign.

Could the equation have been:

y = a(x-h)^2 + k

(note the "=" sign following 'y')

 

[syncmaster913n]

Thank you. I just assumed they meant "is equal to zero". The equation as you see it is a screenshot from the e-book, so this is how it is presented. I figured something must be wrong somewhere but at this stage of my math education I'd much rather assume I'm the one who's wrong, rather than the book, until proven otherwise.