ElectricPavlov

https://web2.0calc.com/questions/equal-complement-or-supplement_1

Here is a VERY similar problem solved:

https://web2.0calc.com/questions/geometry_92608

complementary angles sum to 90 degrees

supplemenatary angles sum to 180 degrees            Can you answer it now?

Day 4     =  14

Day 6     =  22        rate of change =   (22-14) lemons / (2 days) = 4 lemons/day

Very similar....see if you can use the same emthod to solve this one

https://web2.0calc.com/questions/parabola_122

What do YOU think it is , smasai ?

I'll start with the vertex (3,1)  fromula for a parabola

     y = a (x-h)^2 + k

     y = a ( x-3)^2 + 1               now pick a convenient point on the graph   .... how about  0,7     sub in to calcualate a

     7 = a ( -3)^2 + 1          shows a = 2/3

y = 2/3 (x-3)^2 + 1      expand

y = 2/3 x^2 -4x + 7       <===== finish from here

(3x + 2)^2 - (8 * 9) = -4x           expand L side

9x^2 + 12x + 4   - 72 = - 4x       simplify

9x^2 + 16x -68 = 0

a = 9      b = 16       c = - 68

\(x = {-b \pm \sqrt{b^2-4ac} \over 2a}\)

\(x = {-16 \pm \sqrt{16^2-4(9)(-68)} \over 2(9)}\)       Plug and chug !

Answer D .

(n-2) * 180 =

(21-2)(180) =

19(180) = ____________ degrees total