Can someone explain how to do problems like
(-2+4) or (4+ -6)

In a circle, a 45° sector has an area of 32π cm2. what is the radius of this circle? 32 cm 12 cm 16 cm 8 cm

Suppose you want just guess at the answers in a 5 question multiple-choice test. each question has 3 responses and only one is correct. what is the probability of getting two questions right just guessing? 20 points 0.3275 0.2753 0.7532 none of the above

Arectangle has a width of 9 units and length of 40 units. what is the length of a diognal. a. 31 unitsb. 39 unitsc. 41 units d. 49 units