1) 6x^2 + 15x + 14x + 35 = (6x^2 + 15x) + (14x + 35) = 3x*(2x+5) + 7*(2x+5) = from this point complete this case ON YOUR OWN.
2) 20x^2 - 15x + 24x - 18 = (20x^2 - 15x) + (24x - 18) = 5x*(4x-3) + 6*(4x-3) = from this point complete this case ON YOUR OWN.
Do #3 and #4 in THE SAME WAY.
#5 has DEFECT in writing.