Answer: 100+10+1
You basically place zeroes instead of the actual digit to find the value of each number.
Example:
855
800+50+5
2(4-d+2d)=12
8-2d+4d=12
8+2d=12
2d=4
d=2
14 boys : 16 girls
but this would have to be simplified also
7:8
No, when you plug is -5 for x and -1 for why, it ends up being -9 not -11. (-5,-1) is not a solution.
Answer:
x = 10 cm, y = 5 cm gives a minimum area of 300 cm^2.
Step-by-step explanation:
V= x^2y = 500
Surface area A = x^2 + 4xy.
From the first equation y = 500/x^2
So substituting for y in the equation for the surface area:
A = x^2 + 4x * 500/x^2
A = x^2 + 2000/x
Finding the derivative:
dA/dx = 2x - 2000x^-2
dA/dx = 2x - 2000/x^2
This = 0 for a minimum/maximum value of A, so
2x - 2000/x^2 = 0
2x^3 - 2000 = 0
x^3 = 2000/ 2 = 1000
x = 10
Second derivative is 2 + 4000/x^3
when x = 10 this is positive so x = 10 gives a minimum value of A.
So y = 500/x^2
= 500/100
= 5.
