Given parameters:
y varies directly as w;
This interpreted implies that as y increases, we increases by a certain factor or amount;
So, y ∝ w
y = kw
where k is the constant of proportionality
Now, given that y = 8 and w = 2
Input in the equation to solve for k;
8 = k x 2
Solving k gives, k = 4
Now to the second part,
if v is directly proportional to w;
v = k w
So v = 4w
The equation that relates v to w is v = 4w
Answer:
1. c. 628 cubic cm
2. c. 502 cubic inches
Step-by-step explanation:
1.) 3.14 x 5^2 x 8
3.14 x 25 x 8 = 628
2.) 3.14 x ( 8/2 )^2 x 10
3.14 x 4^2 x 10
3.14 x 16 x 10 = 502.4
One, Three and Four are right answers.
Let the number be n.
Then:
n^2 + (1/n)^2 = 82/9; find n. Find the LCD; it is 9n^2.
Mult all 3 terms by 9n^2:
82*9n^2
9n^4 + 9 = (82/9)(9n^2) => 9n^4 + 9 = ------------
9
Then 9n^4 - 82n^2 + 9 = 0
I used my graphing calculator to find that n = 3.
Let's check: is 3^2 + (1/3)^2 = 82/9?
Is 9 + 1/9 = 82/9?
Is 81 + 1 = 82? YES. So, n=3 is a solution.
It would be 500,000 when rounded to nearest thousands.
