Find the length and breadth of a rectangle whose perimeter is 26m and area is 30m^2
Answers
Answer:
perimeter=26m
2(l+b)=26m
l+b=13m
l=13-b (1)
area=30m²
l*b=30
(13-b)b=30
13b-b²=30
b²-13b+30=0
b²-3b-10b+30=0
b(b-3)-10(b-3)=0
b-10)(b-3)=0
b-10=0 and b-3=0
b=10m or b=3m
if b=10m, l=13-10= 3m
if b=3m, l=13-3= 10m
Step-by-step explanation:
- Perimeter of rectangle = 26 m
- Area of rectangle = 30 m²
- Length of the rectangle
- Breadth of the rectangle
Let the length of the rectangle be x m.
Let the breadth of the rectangle be y m.
We know that perimeter of a rectangle is calculated using the formula,
Substitute the given values,
=> 26 = 2 ( x + y)
=> 26 = 2x + 2y
Dividing throughout by 2,
=> 13 = x + y
=> x + y = 13
=> y = - x + 13 ----> 1
Now, we have the area of the rectangle. So by using the formula for area of a rectangle we will obtain our second equation.
We know that the area of the rectangle is calculated using the formula,
Plug in the values,
=> 30 = (x) (y)
Substitute value of y from equation 1,
=> (x) ( - x + 13) = 30
=> - x² + 13x - 30 = 0
Dividing throughout by -1,
=> x² - 13x + 30 = 0
=> x² - 10x - 3x + 30 = 0
=> x ( x - 10) - 3 ( x - 10) = 0
=> (x - 10) = 0 OR (x - 3) = 0
=> x - 10 = 0 OR x - 3 = 0
=> x = 10 OR x = 3
Length = x = 10 m OR 3 m
When x = 10,
Breadth = y = - x + 13
Breadth = y = - 10 + 13 = 3 m
When x = 3,
Breadth = y = - x + 13
Breadth = y = - 3 + 13 = 10 m