Which quadratic equation has root -6 and 5? x^2+6x-5=0
x^2+5x-6=0
x^2-x+30=0
x^2+x-30=0

If f(x)=3x+1 and f^-1=x-1/3, then f^-1(7)=

On a string instrument, the length of a string varies inversely as the frequency of its vibrations. an 11-inch string has a frequency of 400 cylces per second. find the frequency of a 10-icnch string.

What is the value of x in the this question ?