Respuesta :
[tex]\bold{\huge{\underline{ Solution }}}[/tex]
Given :-
- Adah wants to buy a rug for room that is 19 feet wide and 26 feet long.
- She wants to leave a uniform strip of floor around the rug
- She can only afford to buy 330 sq. feet carpet.
To Find :-
- We have to find the dimensions of the rug .
Let's Begin :-
Here, we have
- The dimensions of Adah room that is 19 feet wide and 26 feet long.
But,
- She wants to leave a uniform strip of floor around the rug.
Therefore,
Let the width of the uniform strip of the floor be x
So, The new dimensions of the room will be
- [tex]\sf{ (19 - 2x)\: \:and \: \: (26 - 2x)}[/tex]
- She can only afford to buy 330 sq.feet
We know that,
Area of rectangle
[tex]\bold{\red{ = Length} }{\bold{\red{\times{ Breath}}}}[/tex]
Subsitute the required values,
[tex]\sf{ ( 19 - 2x) }{\sf{\times{(26 - 2x) = 330}}}[/tex]
[tex]\sf{19(26 - 2x) }{\sf{\times{ - 2x (26 - 2x) = 330}}}[/tex]
[tex]\sf{ 494 - 38x - 52x + 4x^{2} = 330 }[/tex]
[tex]\sf{ 494 - 38x - 52x + 4x^{2} = 330 }[/tex]
[tex]\sf{ - 90x + 4x^{2} = 330 - 494 }[/tex]
[tex]\sf{ - 90x + 4x^{2} = - 164 }[/tex]
- Arrange the given terms in general quadratic equation that ax² + bx + c = 0
[tex]\sf{ 4x^{2} - 90x + 164 = 0 }[/tex]
[tex]\sf{ 4x^{2} - 82x - 8x + 164 = 0 }[/tex]
[tex]\sf{ 2x( 2x - 41 ) -4( 2x - 41 ) = 0 }[/tex]
[tex]\sf{ (2x - 4) ( 2x - 41) = 0}[/tex]
[tex]\sf{ x = 2 , x = }{\dfrac{41}{2}}[/tex]
- We can only take only 1 value that is x = 2 because 41/2 will give negative result and dimensions of rectangle can never be negative.
Therefore,
Length of the rug
[tex]\sf{ (19 - 2x) = 19 - 2(2)}[/tex]
[tex]\sf{ = 19 - 4}[/tex]
[tex]\sf{ = 15\: feet}[/tex]
Breath of the rug
[tex]\sf{ (26 - 2x) = 19 - 2(2)}[/tex]
[tex]\sf{ = 26 - 4}[/tex]
[tex]\sf{ = 22\:feet}[/tex]
Hence, The dimensions of the rug are 15 feet and 22 feet.