please help me to sort out these squares
Two squares have sides x cm and ( x+ 4 ) cm .The sum of their squares is 656 sq cm .
Find the sides of the squares.
PLEASE FAST
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Let the side of the smaller square = x cm.
Then the side of the larger square = (x + 4)cm.
Given that sum of their squares = 656 sq.cm.
x^2 + (x + 4)^2 = 656
x^2 + x^2 + 16 + 8x = 656
2x^2 + 8x = 656 - 16
2x^2 + 8x = 640
2x^2 + 8x - 640 = 0
x^2 + 4x - 320 = 0
x^2 + 20x - 16x - 320 = 0
x(x + 20) - 16(x + 20) = 0
(x + 20)(x - 16) = 0
x + 20 = 0 (or) x - 16 = 0
x = -20, x = 16.
Since x cannot be -ve, so x = 16
Hence,
The side of the smaller square = 16cm.
Side of the larger square = x + 4
= 16 + 4
= 20cm.
Sides of the square = 16^2 + 20^2
= 256 + 400
= 656.
Hope this helps!
Then the side of the larger square = (x + 4)cm.
Given that sum of their squares = 656 sq.cm.
x^2 + (x + 4)^2 = 656
x^2 + x^2 + 16 + 8x = 656
2x^2 + 8x = 656 - 16
2x^2 + 8x = 640
2x^2 + 8x - 640 = 0
x^2 + 4x - 320 = 0
x^2 + 20x - 16x - 320 = 0
x(x + 20) - 16(x + 20) = 0
(x + 20)(x - 16) = 0
x + 20 = 0 (or) x - 16 = 0
x = -20, x = 16.
Since x cannot be -ve, so x = 16
Hence,
The side of the smaller square = 16cm.
Side of the larger square = x + 4
= 16 + 4
= 20cm.
Sides of the square = 16^2 + 20^2
= 256 + 400
= 656.
Hope this helps!
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