Rational of course, every natural number, full number and every number that can be written as fraction are rational
The angle is 90 because that' s a right angle.
24 is the answer for your problem
Y= 1x + 8
both is increasing by one
M is the slope, so, y=mx or y=2x. If y is 8 then x is 4.
y=6 x=r
6÷2=3, so r=3.
hope this helps and sorry if it got confusing.