Check the picture below.
since chords NQ and MP cross the center of the circle at R, that means that those two chords are diametrical chords and the angles made by both are vertical angles and thus twin angles, namely both are 18° as you see in the picture, so the angle NMP in magenta is really 162° + 18° + 18° = 198°, and we know the radius NR is 8.
![\textit{arc's length}\\\\ s=\cfrac{r\pi \theta }{180}~~ \begin{cases} r=radius\\ \theta =\stackrel{degrees}{angle}\\[-0.5em] \hrulefill\\ r=8\\ \theta =198 \end{cases}\implies s=\cfrac{(8)\pi (198)}{180}\implies s\approx 27.6](https://tex.z-dn.net/?f=%5Ctextit%7Barc%27s%20length%7D%5C%5C%5C%5C%20s%3D%5Ccfrac%7Br%5Cpi%20%5Ctheta%20%7D%7B180%7D~~%20%5Cbegin%7Bcases%7D%20r%3Dradius%5C%5C%20%5Ctheta%20%3D%5Cstackrel%7Bdegrees%7D%7Bangle%7D%5C%5C%5B-0.5em%5D%20%5Chrulefill%5C%5C%20r%3D8%5C%5C%20%5Ctheta%20%3D198%20%5Cend%7Bcases%7D%5Cimplies%20s%3D%5Ccfrac%7B%288%29%5Cpi%20%28198%29%7D%7B180%7D%5Cimplies%20s%5Capprox%2027.6)
Answer:
120
240
Step-by-step explanation:
We call the length of first part x
Length of second part = y
In the first scenario, it took the tortoise 110 sec to walk the first part and crawl the second.
So,
We have this equation,
x/4 + y/3 = 110
We take the LCM
(3x + 4y)/12 = 110
When we cross multiply
3x + 4y = 110x12
3x + 4y = 1320 ----- equation 1
For scenario 2
x/3 + y/4 = 100
When we take the LCM
(4x + 3y)/12 = 100
We cross multiply
4x + 3y = 100x12
4x + 3y = 1200 ------ equation 2
We now have two equations and we will solve for x and y using simultaneous linear equation.
3x + 4y = 1320 ----- 1
4x + 3y = 1200 ----- 2
We subtract equation 2 from 1 to get
- x + y = 120
We make y subject
y = x + 120 ----- 3
We put the value of y in equation 3 into equation 1
3x + 4(x + 120) = 1320
3x + 4x + 480 = 1320
7x + 480 = 1320
7x = 1320-480
7x = 840
We divide through by 7
x = 840/7
x = 120
We put value of x in equation 3
y = x + 120
y = 120 + 120
y = 240
120 and 240 are the lengths of the 2 parts of the journey.
Thanks
Answer:
in short, Yes they are always rational.
here's why...
E.g. suppose 
and 
are fractions, that means that a,b,c,d are all integers, and b and d are not zero. finding the sum the numerator, and denominator would also have to be integers. the denominator of the sum can't be zero since the denominators of the fractions were not zero, and would give 
and since they are bound by addition (sum means addition) they must also be rational since eit would equal a bigger integer than initially had
Step-by-step explanation:
Simplifies to y=2x-12. slope intercept form is y=MX+b where m is slope and b is intercept do slope 4 and y intercept is -12
