Mathematics
Melani42
2016-04-12 19:52:42
A rectangle is 6 centimeters longer than is wide and has an area of 280 square centimeters if l represent the length,in centimeters of the rectangle solving which of the following formulas will give the correct value for l?
ANSWERS
jordansthatkid
2016-04-12 22:25:12

A = L * W W = L - 6 280 = L(L - 6) or 280 = L^2 - 6L

TandyTalleut
2016-04-12 22:26:27

l = w+6 a = 280 = w*(w+6) 280 = w^2+ 6w. 0 = w^2 + 6w - 280 w^2 + 20w - 14w - 280 (w^2 + 20w) - (14w-280) w(w + 20) - 14(w + 20) 0 = w - 14 OR 0 = w + 20 -20=w OR 14=w 14 must be the answer, you cannot have negative width. Ergo, length = 20. Width + 6, 14 + 6, 20 = length

ADD ANSWER