Answer:
4
Step-by-step explanation:
x equals 4 when y equals 9 on that line
Arrange in ascending order:-
6 7 11 13 14 15 15 19 21
median = 14
lower quartile = mean of 7 and 11 = 9
upper quatile = mean of 15 and 19 = 17
Interquartile range = 17 - 9 = 8
answer is 8
The question is too general....but it could be acute, obtuse
Point-slope form of equation is: 
Step-by-step explanation:
Given points are:
(2,-8) and (1,7)
First of all we have to calculate the slope of the line
so,

Point-slope form is given by:

Putting the value of slope

We can put any one of two given points in the equation to find the final form of point-slope form
So
Putting (1,7) in the equation

Hence, point-slope form of equation is: 
Reducing and simplifying

Keywords: Point-slope form, equation of line
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