Factor out the GCF: 7x2+14x7x^2 + 14x7x2+14x.
7x(x+2)7x(x + 2)7x(x+2)
7(x2+2x)7(x^2 + 2x)7(x2+2x)
x(7x+14)x(7x + 14)x(7x+14)
14x(x+1)14x(x + 1)14x(x+1)