Which rotation maps point K(8,-6) to K'(-6, -8)? 180° counterclockwise rotation
90° clockwise rotation
90° counterclockwise rotation
180° clockwise rotation

Write numerical coefficient of y² in the expression 2x² - 15xy – 7y²

Sanya noticed that the temperature was falling at a steady rate of 1.4 degrees every hour from the time that she first checked her outdoor thermometer. by 6 a.m., the temperature had fallen 21 degrees. which expression can you use to find how many hours earlier she had first checked the thermometer?

The? half-life of a radioactive substance is 20 years. if you start with some amount of this? substance, what fraction will remain in 120 ? years