Answer:
look at explanation
Step-by-step explanation:
To solve all of these questions you just need to scale. While scaling you can divide or multiply.
1.
(divide by 4 to get unit rate)
unit rate = 
2. If it takes one hour to travel 40 miles, then we don't have to scale or anything. We know
, the answer is...
"It'll only take one hour to travel 40 miles. This is correct because the unit rate is
. "
3. Knowing that the constant speed of the plane is
, we can scale then add half of the unit rate to get our answer.
x 3 =
800 x 3 = 2400
then add half of unit rate which is
= 400
so, our answer is 
4.
<--- ( divided by 2)
( multiplied x 2.5) ---> 
To get an easier way to find the answer, if possible you can scale back farther than the 1 hour mark.
Elmer would take 2 and a half hours to ride 15 km.
5. The boys speed is
. All we need to do is divide by 2.
= 4
Answer:
C
Step-by-step explanation:
since there cant be technically half of someone (i hope not) the domain has to be "whole numbers". hours can be split, so they are "all numbers". well, looking at it again, it is C, since the others can not possibly be correct.
Answer:

Step-by-step explanation:
From the question we are told that
Matrix is given as 
Generally let the change in matrix be given as X

Matlab output
![A=[2 -1 10;-3 8 4]\\a=(A(1,1)*-A(1,2))+A(1,2)\\b=(A(2,1)*-A(1,2))+A(2,2)\\X=[A(1,1) a A(1,3); A(2,1) b A(2,3)]\\](https://tex.z-dn.net/?f=A%3D%5B2%20-1%2010%3B-3%208%204%5D%5C%5Ca%3D%28A%281%2C1%29%2A-A%281%2C2%29%29%2BA%281%2C2%29%5C%5Cb%3D%28A%282%2C1%29%2A-A%281%2C2%29%29%2BA%282%2C2%29%5C%5CX%3D%5BA%281%2C1%29%20a%20A%281%2C3%29%3B%20A%282%2C1%29%20b%20A%282%2C3%29%5D%5C%5C)
Generally the matrix that makes row 2 of matrix A equal to first row of A multiplied by the negative of the first element of row 2 plus the original row is

Answer:
90 students
Step-by-step explanation:
Set up a proportion
3/7 = x/210 cross multiply and solve for x
3.14 of 100 =314 that the answer