sum of the areas of two squares is 468m2 if the difference of their perimeter is 24m find the sides of the two squares
Answers
Answer:-
Let the side of first square be a m and side of second square be b m.
Given:-
Sum of the areas of two squares = 468 m²
We know that,
Area of a square = (side)²
So,
⟹ a² + b² = 468 m² -- equation (1)
Also given that,
Difference between their perimeters = 24 m.
We know,
Perimeter of a square = 4 × side
So,
⟹ 4a - 4b = 24
⟹ 4(a - b) = 24
⟹ a - b = 24/4
⟹ a - b = 6
⟹ a = 6 + b
Putting the value of a in equation (1) we get,
⟹ (6 + b)² + b² = 468
using (a + b)² = a² + b² + 2ab in LHS we get,
⟹ (6)² + b² + 12b + b² - 468 = 0
⟹ 2b² + 12b - 432 = 0
⟹ 2(b² + 6b - 216) = 0
⟹ b² + 6b - 216 = 0
⟹ b² + 18b - 12b - 216 = 0
⟹ b(b + 18) - 12(b + 18) = 0
⟹ (b - 12)(b + 18) = 0
★ b - 12 = 0
⟹ b = 12 m
★ b + 18 = 0
⟹ b = - 18 m
Side of a square can't be negative. so, - 18 is neglected.
Substitute b = 12 in equation (1).
⟹ a² + (12)² = 468
⟹ a² = 468 - 144
⟹ a² = 324
⟹ a = 18 m
∴
- Side of first square (a) = 18 m
- Side of second square (b) = 12 m
Answer:
Given :-
- Sum of area of two square = 468 m²
- Perimeter = 24 m
To Find :-
Sides
SoluTion :-
According to the question
Let the two square be x and y.
x² + y² = 468 (1)
4x - 4y = 24
4(x - y) = 24
x - y = 24/4
x - y = 6
x = 6 + y (2)
Now,
Applying Identity (a + b)² = a² + 2ab + b²
Now,
(6)² + y² + 12y + y² - 468 = 0
2y² + 12y - 432 = 0
2(y² + 6y - 216) = 0
y² + 6y - 216 = 0
- Spilting middle term
y² + (18y - 12y) - 216 = 0
y(y + 18) - 12(y + 18) = 0
(y - 12)(y + 18) = 0
Now,
Length of square can't be negative
y = 12
Now,
x² + 12² = 468
x² + 144 = 468
x² = 324
x = √324
x = 18