It's A.............................
You could put,
19
+ 6
———
25
Then write,
19+6=25
Use a number line to add and subtract. With multiplying and dividing just do it like a whole number. But remember, you take the sign of the larger number (example: -20 + 9 = -29). And when there is two negatives (interger)it equals a positive.I hope this helps!
