Can someone
evaluate each expression for r= -3 and s= 5.
r=-3
answer=

It is asking you to substitute or plug in the values. 

Example:

 Evaluate 3r(s+3) if r = -3 and s = 5

See that r? It means that you put in -3 in place of the r, and you put 5 in place of the s so it looks like this:

3*-3(5+3)

Now solve that using order of operations and you should get 
-9*(5+3)  (don't forget that your'e distributing here FIRST then add)

-45+-27

-72

That's how you solve an expression like that. This is only an EXAMPLE. Hope it helped.

This polygon has 4 sides
180(4-2) = 180(2) = 360 degree
80+90+2x + 3x = 360
170+5x = 360
5x = 190
x= 38
measure of angle t is 2(38)= 76
the answer is c. trust me
hope this !