Question 411267: hi, the length of a rectangle is 6 more than its witdth, the area is 72 cm^2, find the height.
i did 1/2*b*h....
1/2(b2+4B)=30
b2+4b=60
b2+4b-60=0
b-6 b+10
b=6 b+-10
is the answer 6 , i am having a hard time confirmting this answer.
thank you in advance for your help
Found 2 solutions by ewatrrr, sudhanshu_kmr:
Answer by ewatrrr(24785)   (Show Source):
You can put this solution on YOUR website!
Hi
length of a 'rectangle' is 6 more than its witdth
Let x and (x+6) represent the width and length respectively
Question states***
x(x+6) = 72 cm^2 |Area of a rectangle is w*l
Solving for x
x^2 + 6x - 72 = 0
factoring
(x+12)(x-6) = 0
(x+12) = 0 x = -12 |tossing out negative solution for a measure
(x -6) = 0 x = 6cm, the width. The length is 12cm (6cm+6)
CHECKING our Answer***
6cm*12cm = 72 cm^2
Answer by sudhanshu_kmr(1152)  (Show Source):
You can put this solution on YOUR website!
what r u doing? what is 1/2*b*h ....?????????
how to find height in rectangle??
Let width = x cm , length = 6+x cm
now, area = length * width
=> 72 = x(6+x)
=> 72 = x^2 + 6x
=> x^2 +6x - 72 = 0
=> x^2 + 12x -6x - 72 = 0
=> x(x+12)-6(x+12) = 0
=> (x-6)(x+12) = 0
so, x= 6, -12
only x = 6cm is possible.....
width = 6 cm, length = 12 cm
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