Answer:
Value of x = 400
Step-by-step explanation:
Joint variation states that describes a situation where a variable depends on two (or more) other variables, and varies directly with some of them.
Given: x varies directly with y and z.
i.e 
and 
then we have the joint variation as;
......[1] where k is the constant variation.
Substitute the value of x =1200 when y =20 and z = 30 to solve for k;
Simplify:
Divide both sides by 600 we get;
Now, substitute k =2 , y =10 and z = 20 to find x;
Using [1] we have;
Therefore, the value of x is, 400
(-x + 7)(x + 5)
Bc if you split -x^2 and 35 into 2 parts to get 2x it’ll be x(7)= 7x & -x(5)= -5x —> 7x-5x=2x
(I hope that made sense?)
Answer:
The length of the shadow is 3.17 feet .
Step-by-step explanation:
Given as :
The height of the person walking on street = H = 5'6''
∴ 12" = 1 '
So, 6" = 
× 6 = 0.5'
I.e H = 5.5 feet
The angle of elevation of from tip of shadow to sun = Ф = 60°
Let The length of the shadow = X feet
<u>Now, From figure</u>'
Tan angle = 
Or, Tan Ф = 
Or, Tan 60° = 
Or, Tan 60° = 
Or, 1.732 =
Or, X = 
∴ X = 3.17 feet
So, The length of the shadow = X = 3.17 feet
Hence, The length of the shadow is 3.17 feet . Answer
If a box has a square base its volume will be:
V=hb^2 where h is the height...
h=V/b^2 we are told that V=125 so
h=125/b^2 now for the surface area, which consists of the two bases for a total of 2b^2. It will also have four sides with a total area of 4(bh)=4bh so
A=2b^2+4bh, using h found above in this gives us:
A=2b^2+4b(V/b^2)
A=2b^2+4V/b
A=(2b^3+4V)/b, then taking the derivatives we can find the velocity of the area function.
dA/db=(6b^3-2b^3-4V)/b^2
dA/db=(4b^3-4V)/b^2
dA/db=0 when 4b^3-4V=0
b^3=V
b=V^(1/3), since V=125
b=5in, and since h=V/b^2
h=125/25=5in
So the dimensions that will minimize the amount of material used to enclose a volume of 125in^2 is a 5in cube.
h=b=5in
The perimeter is the sum of the lengths of all sides.
Find the lengths of the sides using the distance formula:
The answer is c. 16.
