What is the area of a triangle with vertices (3,0) (9,0) (7,6)

Which shows the image of rectangle abcd after the rotation (x, y) → (–y, x)?

Suppose that a households monthly water bill (in dollars) is a linear function of the amount of water the household uses (in hundreds of cubic feet, hcf). when graphed, the function gives a line with slope of 1.65. if the monthly cost for 13 hcf is $46.10 what is the monthly cost for 19 hcf?

If chord ab is congruent to chord cd, then what must be true about ef and eg?