Answer:
The difference is 
Step-by-step explanation:
We must find the common denominator of the fractions.
The common denominator of
and
is
; therefore we have


now it is easy to subtract
using the number line: we have to move
units to the left in order to get to
.
Thus our answer is

Answer:
first and second one, and fourth one
Step-by-step explanation:
Answer:
b = -a
Step-by-step explanation:
Since a and b are equally distant to zero but in opposite directions, a and b are opposites, or additive inverses.
The sum of additive inverses is zero.
a + b = 0
b = -a
Answer:
A
Step-by-step explanation:
Compare the images to 90°, which is right angle, and forms an L. A is just past 90°, B is past 270°, and C is less than 90°.
Answer:
46
Step-by-step explanation:
89