Quadratic Functions. Algebra 1

Step-by-step explanation:

11. Write in point slope form first;

y+4 = (x+1)^2; Convert to standard form;

y=x^2+2x+1-4

y = x^2+2x-3; Final standard form

12. Convert the original point-slope form with the vertex given;

y-3 = a(x-4)^2; plug in the point (1,12) to solve for a;

12 -3 = a(1-4)^2

9 = 9a

a = 1

y-3 = (x-4)^2

y=(x-4)^2+3: Final vertex from

13. The vertex is at (-1,-4)

y +4= (x+1)^2; Factored form can mean many things;

this is the equation of the function; factor it how your teacher taught you.

$13.75 is 100% of the bill
We want 5%
5% out of 100%
5/100 = 1/20
To find 5%, we need to divide by 20
$13.75 / 20 = $0.6875
We can only have 2 decimal places with money, as 7 is above 5 we round 8 up to 9
5% = $0.69

To find the total, add the tax to the original cost
$13.75 + $0.69 = $14.44