Your equation

is in the form

The vertex only relies on "a" and "b" though, so that +9 doesn't really matter in this case. The vertex of a parabola is located where

So your x-coordinate is -1. You need to find f(-1) to find your y-coordinate, and then you list it in the form (-1, y).
Answer:
not really good at maths. 15.33
Step-by-step explanation:
3(x-5)-7=3×8
3x-15-7=24
3x =24+15+7
3x = 46
Three will divide it's self to give you one and divide 46 to give you 15.333
(correct me if i'm wrong)
Step-by-step explanation:
The Answer should be 10 as the diving board is the same distance above the surface which is 10
Answer: 11
Step-by-step explanation:
48+4=52
5×11=55
She needs 11 boxes to cover all expenses.