Answer:
6
Step-by-step explanation:
Use the linear slope formula to solve for m:
m=(y2-y1)/(x2-x1)
using the points (-1,1) and (1,5) you can find the slope for the first interval:
m=(5-1)/(1-(-1))
m=4/2
m=2
you can double check by using the same formula on the second interval, which is (1,5) to (3,9).
m=(9-5)/(3-1)
m=4/2
m=2
therefore, the rate of change is 2.
Let's write an inequality, such as follows: x < sqrt(50) < y. Square both sides of the equation. We get x^2 < 50 < y^2. Obviously, x is between 7 and 8. Also notice, that for integers a,b, (ab)^2/b^2, equals a^2. So let's try values, like 7.1. Using the previous fact, (7.1)^2, equals (71)^2/100. So, (7.1)^2, equals 50.41. Thus, our number is between 7 and 7.1. We find, with a bit of experimentation, that the square root of 50, is 7.07.