Which expression is equivalent to 13 - (-21) ? Choose 1

(Choice A) 
13 + 21

(Choice B) 
-21 - 13

(Choice C)
-13+21

(Choice D)
-21+13

Choice A

Step-by-step explanation:

Negative times negative equals positive, is -21 would change to positive 21

Hope this helps!

step-by-step explanation:

in the absence of parentheses, i will have to make some assumptions:   i interpret your (3x+5/y^6)(4y^3/5)​ to mean:

3x + 5     4y^(3/5)       (3x + 5)(4)

* =

    y^6             1               y^(6-3/5)

if this is not what you expected, repost your question using parentheses to indicate whether you meant

4y^3

    or   4y^(3/5)

    5

its 4 because 2 times 2 is 4, if you double the number two you get four