What two numbers multiply to -16 and add to 6

If the speed of an electromagnetic wave is 100,000 cm/s and its wavelength is 100 cm, what is its frequency? a) 100,000 cycles per second (hz) b) 1 × 10-3 cycles per second (hz) c) 10,000,000 cycles per second (hz) d) 1,000 cycles per second (hz)

What is the value of x? enter your answer in the box.

Which of the following is best modeled using a linear equation y=ax+b, where a is less than 0?