How many different ways can an isosceles trapezoid be reflected across a line of symmetry so that it carries onto itself?

A)0
B)1
C)2
D)4

Cam bought some used books for $4.95. he paid $0.50 each for some books and $0.35 each for the others. he bought fewer than 8 books at each price. how many books did cam buy?

Thales was an ancient philosopher familiar with similar triangles. one story about him says that he found the height of a pyramid by measuring its shadow and his own shadow at the same time. if the person is 5-ft tall, what is the height of the pyramid in the drawing?

What happens to the area as the sliders are adjusted? what do you think the formula for the area of a triangle is divided by 2?