GMAT数学题求教 （貌似要解1元2次方程）The figure shows a square patio surrounded by a walkway of width x meters. If the area of the walkway is 132 square meters and the width of the patio is 5 meters greater than the width of the walkw

GMAT数学题求教 （貌似要解1元2次方程）
The figure shows a square patio surrounded by a walkway of width x meters. If the area of the walkway is 132 square meters and the width of the patio is 5 meters greater than the width of the walkway, what is the area of the patio, in square meters?
A.\x0556
B.\x0564
C.\x0568
D.\x0581
E.\x05100
1元2次方程不太会解了 解了半天没解出来 请说明过程 谢谢.

英语好有优势啊 设宽x 中间的正方形长x+5 可列出方程（2x+x+5）平方-（x+5）平方=132
化简得 2x方+5x-33=0 因式分解 （2x+11）（x-3）=0
x1=-5、5「舍去」 x2=3符合
所以小正方形边长8米
所以面积64 选b 打字不容易

设大正方形边长A，小正方形（patio）边长B
A-B=2x= the width of the walkway
the area of the walkway is 132 square meters：132=A平方-B平方=2Ax+2Bx-------①
the width of the patio is 5 meters greater than the width ...

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设大正方形边长A，小正方形（patio）边长B
A-B=2x= the width of the walkway
the area of the walkway is 132 square meters：132=A平方-B平方=2Ax+2Bx-------①
the width of the patio is 5 meters greater than the width of the walkway：B-x=5
A=3x+5 B=x+5 代入①
得A和B
the area of the patio=B的平方

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A.64
x=3
大正方形面积是196，边长是14

设X为走道宽度，那么露台就是X+5，庭院长为X+X+（X+5）=3X+5
如题可得，
(3X+5)x(3X+5)- (X+5)x(X+5)=132
(9XX+30X+25)-(XX+10X+25)=132
合并同类项 8XX+20X=132
16XX+40X=264
16XX+40X+5x5=264+5x5...

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设X为走道宽度，那么露台就是X+5，庭院长为X+X+（X+5）=3X+5
如题可得，
(3X+5)x(3X+5)- (X+5)x(X+5)=132
(9XX+30X+25)-(XX+10X+25)=132
合并同类项 8XX+20X=132
16XX+40X=264
16XX+40X+5x5=264+5x5
(4X+5)x(4X+5)=289
4X+5=17
X=3
那么庭院的面积是(3+5)x(3+5)=8x8=64

B.64

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