This is the term in a polynominal without a variable

The angle of a triangle are given as 6x,(x-3), and (3x+7). find x then find the measures of the angles

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 this system of equations. 12x − 18y = 27 4x − 6y = 10