4) The sum of the areas of two squares is 400 sq.m. If the difference between their perimeter is 16 m. , what are the sides of two squares
Answers
Step-by-step explanation:
assume that the side of square 1 is S1 and side of square 2 is S2. then, S1 = 16m and S2 = 12m
Given data :-
- The sum of the areas of two squares is 400 m².
- the difference between their perimeter is 16 m.
Solution:-
Let, x be the side of first of square. & y be the side of second square.
We know formulae of area & perimeter of square.
→ Area of square = (side)²
→ Area of first square = ( x )² ....[1]
→ Area of second square = ( y )² ....[2]
→ Perimeter of square = 4(side)
→ Perimeter of first square = 4x ....[3]
→ Perimeter of second square = 4y ....[4]
{Accodring to given}
For area of square
{from eq. [1] & eq. [2]}
→ ( x )² + ( y )² = 400 .....[5]
{Accodring to given}
For perimeter of square
{from eq. [3] & eq. [4]}
→ 4x - 4y = 16
→ 4(x - y) = 16
→ (x - y) = 16/4
→ x - y = 4
→ x = 4 + y .....[6]
Put value of x in eq. [ 5 ]
→ ( x )² + ( y )² = 400
→ ( 4 + y )² + ( y )² = 400
{By algebric identity}
→ (4² + [2 × 4 × y] + y² ) + y² = 400
→ 16 + 8y + y² + y² = 400
→ 2y² + 8y + 16 = 400
→ y² + 4y + 8 = 200
→ y² + 8y + 8 - 200 = 0
→ y² + 8y - 192 = 0
→ y² + 16y - 12y - 192 = 0
→ y (y + 16) - 12 (y + 16 ) = 0
→ (y + 16) - (y - 12) = 0
→ y + 16 = 0 or y - 12 = 0
→ y = - 16 or y = 12
We know that side of square is can not negative hence,
→ y = 12 & y ≠ - 16
Hence,side of first square is 12 m.
Put value of y in eq. ( 6 )
→ x = 4 + y
→ x = 4 + 12
→ x = 16 m