Question

The temperature of a liquid decreases steadily over several hours. If you calculate the total change in temperature after several hours, will your answer be positive or negative? Explain using the sign rules of multiplication or division

Answer 1

I think positive...your temperature can decline from 10 degrees to -20 degrees, but the change in temperature is 30 degrees.

positive x positive = positive
negative x negative = positive
positive x negative = negative

an odd number of negative signs in a multiplication or division problem make the answer negative
an even number of negative signs in a multiplication or division problem make the answer positive