Ifabcd is a parallelogram, find the value of x
19x - 31
11x+1

Using only the digits 5, 6, 7, 8, how many different three digit numbers can be formed if no digit is repeated in a number?

Which has the greater energy, light of wavelength 519 nm or light with a frequency of 5.42 x 10^8 sec^-1?

Talia grouped the terms and factored out the gcf of the groups of the polynomial 15x2 – 3x – 20x + 4. her work is shown below. (15x2 – 3x) + (–20x + 4) 3x(5x – 1) + 4(–5x + 1) talia noticed that she does not have a common factor. what should she do?