To increase or decrease an amount by 30% what single multiplier would you use?

How do you find the circumfrance of a circle?

Candy lives in the center of town. her friend darlene lives 28 miles to the east and her friend dana lives 21 miles north. approximately how far do dana and darline live apart ?

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15