Solve the following questions. (Any two)
Sum of areas of two squares is 244 cm² and the difference between their perimeter is 8 cm.
Find the ratio of their diagonals.
i.
Answers
Step-by-step explanation:
Given:-
Sum of areas of two squares is 244 cm² and the difference between their perimeter is 8 cm.
To find:-
Find the ratio of their diagonals.
Solution:-
Let the side of the first square be X cm
Let the side of the second square be Y cm
(X > Y)
Area of the first square = Side ×Side= X^2 sq.cm
Area of the second square = Y^2 sq.cm
Sum of areas of two squares = X^+Y^2 sq.cm
According to the given problem
Sum of areas of two squares = 244 cm^2
=>X^2 + Y^2 = 244 ---------(1)
Perimeter of a square = 4× length of the side
Perimeter of the first square = 4X cm
Perimeter of the second square = 4Y cm
Their difference = 4X-4Y cm
According to the given problem
The difference between Perimeters of the two squares = 8 cm
=>4X-4Y=8
=>4(X-Y)=8
=>X-Y =8/4
=>X-Y = 2 cm -------------(2)
We know that
(a-b)^2 = a^2 -2ab +b^2
=>(X-Y)^2 = X^2 -2XY +Y^2
=>2^2 = 244-2XY
=>4-244 =-2XY
=>-240 = -2XY
=>XY = -240/-2
XY = 120 -------------(3)
(X+Y)^2 = X^2+Y^2+2XY
=>(X+Y)^2 = 244+2(120)
=>(X+Y)^2 = 244+240
=>(X+Y)^2 = 484
=>X+Y = √484
X+Y= 22------------(4) (taking positive)
From (2) &(4)
X+Y = 22
X-Y = 2
(+)
________
2X+0=24
________
=>2X=24
=>x=24/2
=>X=12
Substituting The value of X in (4) then
=>12+Y = 22
=>Y=22-12
=>Y=10
The values of X = 12 and Y=10
Side of the first square = 12 cm
Diagonal of a square = √2 ×side
Diagonal of the first square = 12√2 cm
Side of the second square = 10 cm
Diagonal of the second square = 10√2 cm
Ratio of their diagonals = 12√2:10√2
=>12:10
=>6:5
Therefore,The ratio = 6:5
Answer:-
The rato of the diagonals of the two squares is 6:5
Check:-
Side of the first square = 12 cm
Area of the first square = 12^2 = 144 sq.cm
Side of the second square = 10 cm
Area of the second square = 10^2
=100 sq.cm
Their sum = 144+100 = 244 sq.cm
Perimeter of first square = 4×12 =48 cm
Perimeter of second square = 4×10 = 40 cm
Their difference = 48-40 = 8 cm
Verified the given relations
Used formulae:-
- Diagonal of a square = √2 ×side
- Area of the first square = Side ×Side
- Perimeter of a square = 4× length of the side
- (a-b)^2 = a^2 -2ab +b^2
- (a+b)^2 = a^2 +2ab+b^2