Explain why when factoring x^2 + 6x + 9, it is not necessary to check the sum of the factor pair -1 and -9 or -3 and -3.

The highest common factor of 132 and 220

Given that de, df, and ef are midsegments of △abc, and de=3.2 feet, ef=4 feet, and df=2.4 feet, the perimeter of △abc is .

What is the factor form of x^2-9x+14