I think that would be 9 I am not sure.
Answer is C hope this helps
X is 15because 15-10=5
x= 3*5
x=15
This is a linear equation y = mx, where:
m= slope or reading rate:
x = the number of minutes
y = the number of pages read.
So the equation becomes: y = 4.5.x
How many minutes it will take to read 90 pages (y):
90 = 4.5.x or x = 90/4.5 and x = 20 minutes
So the ordered pair will be (20,90)