The area of the room is 70 square meters. determine its length and width.
2007-05-17 15:20:19 · 6 answers · asked by ohoma 1 in Science & Mathematics ➔ Mathematics
x(x + 3) = 70
x^2 + 3x = 70
x^2 + 3x - 70 = 0
(x + 10)(x - 7) = 0
x = -10 or 7
since you can't have negative distance
Length = 10m
Width = 7m
2007-05-17 16:46:03 · answer #1 · answered by Sherman81 6 · 0⤊ 0⤋
Quadratic Version:
let the width be x
x(x+3) = 70
x^2+3x-70=0
(x+10)
(x-7)
(x-7)(x+10)=0
x -7 = 0
x = 7
x+10=0
x = -10
(-) rejected
Hence, if the width = 7m, length = 10m
2007-05-18 02:09:52 · answer #2 · answered by Kuan T 2 · 0⤊ 0⤋
Lenght 10 meters, width 7 meters
2007-05-17 22:28:22 · answer #3 · answered by dardee_13 1 · 0⤊ 0⤋
area = l*w
l=w+3
so area = (w+3)*w = 70
w² + 3w = 70
w² + 3w - 70 = 0
(w+10)(w-7)=0 This is true only when w+10=0 (w=-10) or w-7=0 (w=7).
Since width can't be negative width=7 and length=10
2007-05-17 22:27:10 · answer #4 · answered by Astral Walker 7 · 0⤊ 0⤋
Only hints;
Let width be 'x';
length =x+3;
area =x*(x+3)=70
Factorise the quadratic.
Best of luck!
2007-05-17 22:31:11 · answer #5 · answered by bamboo 2 · 0⤊ 0⤋
let width = w
length = w + 3
w.(w + 3) = 70
w² + 3w = 70
w² + 3w - 70 = 0
(w + 10).(w - 7) = 0
w = 7 is acceptable answer.
Width = 7 m
Length = 10 m
2007-05-18 02:46:27 · answer #6 · answered by Como 7 · 0⤊ 0⤋