Over what interval is the function decreasing? f(1) = x2 + 2x + 2​

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)

Solve for x and y: 217x + 131y = 913; 131x + 217y = 827

I'm confused on this could anyone me and show me what i need to do to solve it.