(a) Fifteen is less than , so subtract and attach a negative sign to the result: −7.
(b) Twenty-seven is less than , so subtract and attach a negative sign to the result: .
(c) Eighty-nine is less than , so subtract and attach a negative sign to the result: .
(d) One thousand is less than , so subtract and attach a negative sign to the result: .
3
(a) To negate , attach a negative sign:
(b) To negate , attach a negative sign: . Now cancel adjacent negative signs: .
(c) Zero is its own negation.
(d) Add first: , and the negation of .
(e) Subtract first: , and the negation of .
(f) Begin by subtracting: , and the negation of .
4
(a) The number is already positive, so the absolute value of .
(b) The number is negative, so the absolute value of .
(c) First, do the addition inside the absolute value bars: , which is positive. The absolute value of .
(d) First, do the subtraction: , which is positive. The absolute value of . You have a negative sign outside the absolute value bars, so negate your answer to get .
(e) Begin by subtracting: , which is negative. The absolute value of .
