Answer:
which grade u r in I'm in 10th grade and Indian
The answer is 31/40
because first you got cane both of the fraction to the same denominator.
72/80 + 70/80
Add 72+70=142.
142/80 change it to an mixed number and it will be 1 31/40 in simplest form.
Answer:

Step-by-step explanation:
We have given the equation y = 6 sin (x)
On differentiating both side 
As it passes through the point 
So 
Now the unit vector is parallel to the tangent so m will be 5.196
This passes through the point 
So unit vector will be 

Answer:
Sqrt 80 = 8.94
Step-by-step explanation:
d = sqrt[(x-x)^2 + (y-y)^2]
d = sqrt [(6-2)^2 + (-9 - - 1)^2]
d = sqrt [(4)^2 + (-8)^2]
d = sqrt (16 + 64)
d = sqrt 80
d = 4 sqrt 5 = 8.94
The answer is 3
Multiply 6 by 3 to get the total amount of money for the books then minus the answer 18 which you get from 6 x 3 = 18
Then minus 18 from 21 to get $3
21 - 18 = 3