Select all the statements that are true. 2.3 + ( - 2.3 ) is equal to zero.

( -3.7 ) + ( -4.1 ) is positive.

-2.6 - ( -12/4 ) is positive.

5/2 + ( -2.5 ) is negative.

72 - ( -100 ) is negative.

The 1st and the 3rd one

Step-by-step explanation:

2.3+(-2.3) ➡ 2.3 -2.3 = 0 ,so this option is correct

-3.7+(-4.1) ➡ -3.7 - 4.1 = -7.8 so this option isn't correct

-2.6-(-12/4) ➡-2.6 + 3 = 0.4 this option is also correct

(5/2)+(-2.5) ➡ 5/2 -5/2 = 0 this  would be undefined because we can't divide 0 by 2 or any other rational numbers

E.72-(-100) ➡72+100= 172  this option is incorrect because 172 is positive

paula, cory, and krista

since your problem is x^4 = 81, what you have to undeo is the "to the fourth power" part.

the inverse (opposite operation) of "to the fourth power" is "to the fourth root".

  (x^4) ^ ¼   = 81 ^ ¼  

  81 = 3^4     so (3 ^ 4) ^ ¼   =   3 ^ 1   = 3

by hand: (3 ^ 4) ^ ¼   =   3 ^ (4 x ¼) = 3 ^ 1   = 3   (when you take a power to a power, multiply the exponents.)

or, do it by calculator. one way of finding the fourth root is to use ^ (1/4)

step-by-step explanation: