ElectricPavlov

3 (x^2+2/3x)   - 4         'complete the square'

3 (x+1/3)^2   - 4 1/3   

5x^2-80x+18 = 0     Quadratic Formula shows roots   x =   8 +- sqrt (1510) / 5

   take it from here......

here are 4 lines on the 3 x 3  page encompassing 12 borders ....  18 / 12 =  1.5 inch side length of stamp

the 6 x 6 will have 10 lines  each covering 6 edges     6 edges x 1.5 inches x 10 = 90 inches

First one   5 .678     nearest whole number  6  (round UP from .5 or above)     nearest 10th  5.7    nearest 100th 5.68

   you try the rest......let us know if you need more help

Well 79.95   is really just ~ 80

  and 45.25 is about  ~ 45       so she spent about     80+45 = $125

80 - 45 = ~$35 more on skates

https://web2.0calc.com/questions/help-please_66339

This is a bowl shaped parabola

minimum occurs at the vertex

'x' at the vertex can be found by   - b /2a =  - -12/6 = 2

sub in 2 for x

3(2^2) -12(2) + k = 1              1 is the minimum value requested in the Q

12   - 24   + k = 1

k = 13

Here is a graph:   (you can see the minumum value is 1 when k = 13)

https://www.desmos.com/calculator/ar7evacrbn

I think the greatest volume will be held by a cube (a square is a rectangle with = sides)

each side (there are 4)      4   x w x w

and the bottom                     w x w              

   total surface area   5 w^2 = 4800

                                         w = depth = ~30.984 ft

volume = 30.984³  =   ......... ft ³

Using only 15 letters in each of the three positions of the initials

15  *  15  * 15 = ..........   combos

First find the equation of the line        slope = 6/-3 = -2

point slope form of the line

  y-5 = -2(x-4)

 y-5 = 8 - 2x

y+2x = 13      divide by 13

y /13  + x / (13/2) = 1