It seems that you have mistakenly typed the wrong equation which is supposed to be 4x^2 - 20x = 0. So given the correct equation, the factor for this one would be this: 4x(x-5) = 0 So let us check. 4x (x) = 4x^2 4x (-5) = -20x Which makes it 4x^2-20x = 0 I hope this answer helps.
105 kg to 90 kg If he looses 50 kg a week it would be about less than 1 wk. If he looses 5 kg a week it would be 3 weeks. He can not loose 500 kg in a week.
