Question 448056
Whenever you have "minus a negative" back to back, that becomes "plus"


3 - (-4) 
= 3 + 4 {minus a negative becomes plus}
= 7


5 - (-3)
= 5 + 3 {minus a negative becomes plus}
= 8


-3 - 4
= -7 {just add 3 and 4 and put a negative in front}


3 - 4 
= -1 {imagine standing on 3, on the number line, and moving 4 to the left}
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