Answer:

Step-by-step explanation:

If it is just the decimal 3.1415 then it is rational. If it is pi it is irrational
x + x+1 + x+2 =81
Simplify:
3x + 3 = 81
Subtract 3 from both sides
3x = 78
Divide both sides by 3
x = 26 or C). 26
Same signs add and keep. Different signs subtract. If you are subtracting take the sign of the number with the higher absolute value