29
PEMDAS
(45/9)+(8*3)
5+24
29
Answer:
The lines ared skew
Step-by-step explanation:
First we check if they are parallel. To do this we compare the ratios of the slopes of each component, and this should be the same:
![\frac{L1_{x} }{L2_{x} } =\frac{L1_{y} }{L2_{y} }= \frac{L1_{z} }{L2_{z} }](https://tex.z-dn.net/?f=%5Cfrac%7BL1_%7Bx%7D%20%7D%7BL2_%7Bx%7D%20%7D%20%3D%5Cfrac%7BL1_%7By%7D%20%7D%7BL2_%7By%7D%20%7D%3D%20%20%5Cfrac%7BL1_%7Bz%7D%20%7D%7BL2_%7Bz%7D%20%7D)
![\frac{-2}{-1} =\frac{4}{3} =\frac{8}{2}](https://tex.z-dn.net/?f=%5Cfrac%7B-2%7D%7B-1%7D%20%3D%5Cfrac%7B4%7D%7B3%7D%20%3D%5Cfrac%7B8%7D%7B2%7D)
As we can see the ratios are different so they are not parallel lines.
Now we test for intersesction:
we have to equate each component and solve it as a system:
- 3-2t=-1-u
- 7+4t=18+3u
- -3+8t=7+2u
From equation 1: u=2t-4 we replace this in eq. 2
From equation 2: t=1/2 replacing both in equation 3 should give us an identity
From equation 3: we reach 1=3 as this is not true, out hypothesis that the lines intersect is wrong.
Since this lines are not paralel and don't intersect we must conclude that the are skew
Ok! So first, 2 hours are 120 minutes and 55 + 35 = 90
120 - 90 = 30
So the answer is A. Cindy spends 30 minutes on History
Hope it helps!
U need to think of the question they are asking you and then when u do u cab find out what the answer is