Remark
The short answer is you multiply 0.6 times the cm/s to get m/min.
Solve
Though you didn't ask for it, here's the way it is done. Notice that each set of brackets cancels the units of a set of brackets to the left of the set of brackets you are observing. This is called unit analysis. The answer is given below.
![\frac{18 cm}{sec} *[\frac{60 cm}{1 min}] * [\frac{1 m}{100 cm}] = 18*0.6\frac{m}{min}=10.8\frac{m}{min}](https://tex.z-dn.net/?f=%20%5Cfrac%7B18%20cm%7D%7Bsec%7D%20%2A%5B%5Cfrac%7B60%20cm%7D%7B1%20min%7D%5D%20%2A%20%5B%5Cfrac%7B1%20m%7D%7B100%20cm%7D%5D%20%3D%2018%2A0.6%5Cfrac%7Bm%7D%7Bmin%7D%3D10.8%5Cfrac%7Bm%7D%7Bmin%7D)
Assume 0 < <em>x</em>/2 < <em>π</em>/2. Then
tan²(<em>x</em>/2) + 1 = sec²(<em>x</em>/2) ===> sec(<em>x</em>/2) = √(1 - tan²(<em>x</em>/2))
===> cos(<em>x</em>/2) = 1/√(1 - tan²(<em>x</em>/2))
===> cos(<em>x</em>/2) = 1/√(1 - <em>t</em> ²)
We also know that
sin²(<em>x</em>/2) + cos²(<em>x</em>/2) = 1 ===> sin(<em>x</em>/2) = √(1 - cos²(<em>x</em>/2))
Recall the double angle identities:
cos(<em>x</em>) = 2 cos²(<em>x</em>/2) - 1
sin(<em>x</em>) = 2 sin(<em>x</em>/2) cos(<em>x</em>/2)
Then
cos(<em>x</em>) = 2/(1 - <em>t</em> ²) - 1 = (1 + <em>t</em> ²)/(1 - <em>t</em> ²)
sin(<em>x</em>) = 2 √(1 - 1/(1 - <em>t</em> ²)) / √(1 - <em>t</em> ²) = 2<em>t</em>/(1 - <em>t</em> ²)
Sum of all exterior angle should be 360.
when the measure of each exterior angle is 36 then it has 10 sides and it is a
<span>Decagon </span>
