Acircle has a radius of 4ft . find the length s of the arc intercepted by a central angle of 156° .

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

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

Look at the figure below: triangle abc is a right triangle with angle abc equal to 90 degrees. the length of ac is 5 units and the length of ab is 4 units. d is a point above c. triangle adc is a right triangle with angle dac equal to 90 degrees and dc parallel to ab. what is the length, in units, of segment cd?