Answer:
Original number is 47
Step-by-step explanation:
Given: The tens digit is three less than the units digit. If the digits are reversed, the sum of the reversed number and the original number is 121.
To find: the original number
Solution:
Let x denotes digit at ones place.
As the tens digit is three less than the units digit,
Digit at tens place = 
Original number = 
When digits are reversed,
Reversed number = 
As the sum of the reversed number and the original number is 121,

So,
original number = 
Answer: Choice D

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Explanation:
Let g(t) be the antiderivative of
. We don't need to find out what g(t) is exactly.
Recall by the fundamental theorem of calculus, we can say the following:

This theorem ties together the concepts of integrals and derivatives to show that they are basically inverse operations (more or less).
So,

From here, we apply the derivative with respect to x to both sides. Note that the
portion is a constant, so 
![\displaystyle F(x) = g(x^2) - g(\pi)\\\\ \displaystyle F \ '(x) = \frac{d}{dx}[g(x^2)-g(\pi)]\\\\\displaystyle F\ '(x) = \frac{d}{dx}[g(x^2)] - \frac{d}{dx}[g(\pi)]\\\\ \displaystyle F\ '(x) = \frac{d}{dx}[x^2]*g'(x^2) - g'(\pi) \ \text{ .... chain rule}\\\\](https://tex.z-dn.net/?f=%5Cdisplaystyle%20F%28x%29%20%3D%20g%28x%5E2%29%20-%20g%28%5Cpi%29%5C%5C%5C%5C%20%5Cdisplaystyle%20F%20%5C%20%27%28x%29%20%3D%20%5Cfrac%7Bd%7D%7Bdx%7D%5Bg%28x%5E2%29-g%28%5Cpi%29%5D%5C%5C%5C%5C%5Cdisplaystyle%20F%5C%20%27%28x%29%20%3D%20%5Cfrac%7Bd%7D%7Bdx%7D%5Bg%28x%5E2%29%5D%20-%20%5Cfrac%7Bd%7D%7Bdx%7D%5Bg%28%5Cpi%29%5D%5C%5C%5C%5C%20%5Cdisplaystyle%20F%5C%20%27%28x%29%20%3D%20%5Cfrac%7Bd%7D%7Bdx%7D%5Bx%5E2%5D%2Ag%27%28x%5E2%29%20-%20g%27%28%5Cpi%29%20%5C%20%5Ctext%7B%20....%20chain%20rule%7D%5C%5C%5C%5C)

Answer is choice D
Answer:
400m(if the length of sides is 100m)
Step-by-step explanation:
4L
4×100
=400m
Answer:
9/10
Step-by-step explanation:
the rule says

so in our case
a=3
b=4
c=5
d=6
so the division is

we can simplify

that's our answer
I don't know if you need step by step of the rule, if you need let me know