SOLUTION: The perimeter of a rectangle is 30cm; the area of the rectangle is 50cm square. Find the length and width of the rectangle.
Please help!
Thanks in advance!
Algebra.Com
Question 304957: The perimeter of a rectangle is 30cm; the area of the rectangle is 50cm square. Find the length and width of the rectangle.
Please help!
Thanks in advance!
Found 2 solutions by mananth, scutechandni10:
Answer by mananth(16946) (Show Source): You can put this solution on YOUR website!
2L+2W= perimeter = 30
L*w =Area = 50
L*W=50 l= 50/w
2L + 2W = 30
2*50/w +2W= 30
100/W + 2W=30
100+2W^2 / w = 30
100+2W^2= 30 W
2W^2-30W+100=0
W^2-15W+50=0
W^2-10W-5W+50=0
W(W-10)-5(w-10)=0
(W-5)(W-10)=0
W= 5 Or 10
The sides of the rectangle are 5 by 10
Answer by scutechandni10(7) (Show Source): You can put this solution on YOUR website!
Perimeter is 30cm
Area= 50cm2
Now,form simultaneous equation;
2l+2w=30
l*w=50
l=50/w
substitute into first equation:
2(50/w)+2w=30
100/w+2w=30
find LCM of w and 1; that is w
Therefore; (100 + 2w square)/w = 30
Multiply by w both sides to cancel(to get rid of) the denominator
w * 100+ 2w square/w = 30 * w
Therefore; 100+2w square = 30w
2w^2 - 30w + 100 = 0
Now this becomes a quadratic equation;
a= 2 b=-30 c= 100
now you substitute the values of a b and c in the formula.
ORR
By factorization;
Splitting the middle term;
2w^2-30w+100=0
2w^2-20w-10w+100=0
(2w^2-20w)+ (-10w+100)=0
2w(w-10)- 10(w-10)=0
Either (2w+10) (w-10) = 0
2w+10=0 w-10=0
2w=-10 w=+10
w= -5
Note: Length or width cannot be in negative therefore length is 10cm and width is 5cm
Note: ^2 means "square"
RELATED QUESTIONS
The perimeter of a rectangle is 30cm and its area is 50cm^2. Find, in centimeters the... (answered by josgarithmetic)
The length of a rectangle is twice its width. If the perimeter of the rectangle is 30cm... (answered by checkley77)
The length of a rectangle is 4 times the width. The perimeter is 50cm. Find the length... (answered by ewatrrr)
if a rectangle has a perimeter of 30cm and the length is twice the width what is the... (answered by oscargut)
The length of a rectangle is four times it's width. If the perimeter of the rectangle is... (answered by Alan3354)
If the area of a rectangle is 30cm and the perimeter is 26cm. What is the length and... (answered by josgarithmetic)
the perimeter and area of rectangle are 22cm are 30cm square respectively. find the... (answered by ankor@dixie-net.com)
If the length of the rectangle is twice the width,and the perimeter of the rectangle is... (answered by JulietG)
the perimeter of a rectangle is 30cm. if the width is 5cm, what is it's... (answered by Theo,MathTherapy,Alan3354)