Henry subracts 16 from it and gets an answer of 13.9 what was the orginal number​

2.1 is the answer for that question

the original number would have been 29.9

Step-by-step explanation:

13.9+16=29.9

i think it's ф or x=6,-6

step-by-step explanation:

-x^2=-36

x^2=-36

ф

or

if you mean by : -(x^2)=-36

it'll be: x^2=36

x=6,x=-6

hope it'll ! have a good day!

you for asking!