Hello from MrBillDoesMath!
Answer:
Choice e (2a)
Discussion:
a - b = 0 => a = b (*)
So
a + b = (b) + a => commutative property and b = a from (*)
= (a) + a
= 2a
which is Choice e.
Thank you,
MrB
Answer:
1. Right: pointing downwards
Left: pointing upwards
2. Right: pointing upwards
Left: pointing upwards
3. Right: pointing downwards
Left: pointing upwards
4a. True
4b. True
Step-by-step explanation:
When the leading coefficient is negative the equation will either open downwards or the y-values will decrease as the x-values increase. The opposite is true for when the leading coefficient is positive. When the degree is odd one end will point downwards while the other points upwards. When the degree is even, both ends point in the same direction.
I hope this helps :)
Answer:
a
Step-by-step explanation:
Joelle walked for 20 minutes and her speed was 3 miles per hour.
So
In 1 hour or 60 minutes Joelle walked for a distance of = 3 miles
Then
In 20 minutes Joelle walked for = (3/60) * 20 miles
= 60/60 miles
= 1 mile
Again
Joelle ran for 15 minutes at a speed of 6 miles per hour
So
In 1 hour or 60 minutes Joelle walked for a distance of = 6 miles
so
In 15 minutes Joelle walked for a distance of = (6/60) * 15 miles
= 15/10 miles
= 3/2 miles
So
The total distance covered by Joelle = 1 + (3/2) miles
= (5/2) miles
= 2 1/2 miles
So Joelle covered a total distance of 2 1/2 miles while walking and running.<span />
It can be useful to know the prime factorization of the number:

Then, remember that the n-th root of a number is the same as that number to the 1/n-th power:
![\sqrt[4]{256} = 256^{\frac{1}{4}}](https://tex.z-dn.net/?f=%20%5Csqrt%5B4%5D%7B256%7D%20%3D%20256%5E%7B%5Cfrac%7B1%7D%7B4%7D%7D)
Finally, you have to remember the rule for raising a power to another power, i.e. you multiply the exponents:

Put together everything we said so far to write
![\sqrt[4]{256} = 256^{\frac{1}{4}} = (2^8)^{\frac{1}{4}} = 2^{\frac{8}{4}} = 2^2 = 4](https://tex.z-dn.net/?f=%20%5Csqrt%5B4%5D%7B256%7D%20%3D%20256%5E%7B%5Cfrac%7B1%7D%7B4%7D%7D%20%3D%20%282%5E8%29%5E%7B%5Cfrac%7B1%7D%7B4%7D%7D%20%3D%202%5E%7B%5Cfrac%7B8%7D%7B4%7D%7D%20%3D%202%5E2%20%3D%204%20)