Answer:
10 cm
Step-by-step explanation:
If we assume that DC is parallel to AB, then triangle DOC is similar to triangle AOB.
However, even with this assumption, there is not enough information in the diagram to solve for DO. We would also need to know the length of CO. Then we could write a proportion:
DO / (DO + 20) = CO / (CO + 24)
Edit: OD is 2 cm shorter than OC. If we call x the length of OD, then the length of OC is x+2.
Putting this into our proportion:
x / (x + 20) = (x + 2) / (x + 2 + 24)
x / (x + 20) = (x + 2) / (x + 26)
Cross multiply:
x (x + 26) = (x + 2) (x + 20)
Distribute:
x² + 26x = x² + 20x + 2x + 40
x² + 26x = x² + 22x + 40
4x = 40
x = 10
So the length of DO is 10 cm.
<h3>Given</h3>
- C(t) = 40 cm + t·(2/5 cm/s) . . . circumference of a circle vs time
<h3>Find</h3>
- dr/dt for radius r
- r at t=4 seconds
<h3>Solution</h3>
The circumference and radius of a circle are related by
... C = 2πr
so the radius in terms of circumference is
... r = C/(2π)
... r(t) = (40 +0.4t)/(2π) = (1/π)(20 cm + 0.2t cm/s)
Then dr/dt is
... dr/dt = 0.2/π cm/s
And the radius at t=4 s is
... r(4) = (1/π)(20 + 0.2·4) cm
... r(4) = 20.8/π cm
Answer:
In standard form x^2/64 + y^2/100 = 1
Step-by-step explanation:
The major axis is the y axis because 10 has a larger value than 8.
8x8 = 64
10 x10 = 100
Answer:
$2766.67
Step-by-step explanation:
415/.15 = 2766.666666666666667