1）The sum of the area s of two circles is 65pi square feet.The length of a radius of the larger circle is one foot less than twice the length of the radius of the smaller circle.Find the length of a radius of each circle.2) The combined area of a s

1）The sum of the area s of two circles is 65pi square feet.The length of a radius of the larger circle is one foot less than twice the length of the radius of the smaller circle.Find the length of a radius of each circle.2) The combined area of a s
1）The sum of the area s of two circles is 65pi square feet.The length of a radius of the larger circle is one foot less than twice the length of the radius of the smaller circle.Find the length of a radius of each circle.
2)
The combined area of a square and a rectangle is 64 square centimeters.The width of the rectangle is 2 cm more than the length of a side of the square and the length of the rectangle is 2 cm more than its width.Find the dimensions of the square and the rectangle.
3)
The Ortegas have an apple orchard that contains 90 trees.The number of trees in each row is 3 more that twice the number of rows.Find the number of rows and the number of trees per row?

1）The sum of the area s of two circles is 65pi square feet.The length of a radius of the larger circle is one foot less than twice the length of the radius of the smaller circle.Find the length of a radius of each circle.2) The combined area of a s
1、大圆小圆面积总和是65,大圆半径比小圆半径的2倍少1,求每个圆半径.
设小圆半径为r,大圆半径为2r-1,
则 πr^2+π(2r-1)^2=65
解出r后再求2r-1即可
2、正方形和矩形面积之和为64.长方形的宽比正方形边长大2,长方形的长比宽多2,求两个图形各自的边长.
解
设长方形宽为x,则长为x+2,正方形边长为x-2
所以
x(x+2)+(x-2)^2=64
2x^2-2x-60=0
x^2-x-30=0
x=6
所以 正方形边长为4,长方形长为8,宽为6.
3、某人有一个苹果园,种有90棵树.每一行苹果树的数量比果园的总行数2倍多3.求每行苹果树的数目以及果园共有多少行.
解
设果园有x行,则每行苹果树为2x+3,
90=x(2x+3)
2x^2+3x-90=0
x=6
所以 共有6行,每行15棵树.

是英文没看懂，还是题目不会做啊？
我简单翻译一下：
1、两个圆的面积和为65π平方英尺，其中大圆的半径是小圆半径的两倍小1英尺。求两圆半径。
设小圆半径为r，大圆半径为R
则有：R=2r-1
两圆面积和为：π*r^2+π(2r-1)^2=65π
解得：r=4英尺（负根舍去）
则大圆半径R=7英尺。
2、一个正方形和一个长方形面积和为6...

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是英文没看懂，还是题目不会做啊？
我简单翻译一下：
1、两个圆的面积和为65π平方英尺，其中大圆的半径是小圆半径的两倍小1英尺。求两圆半径。
设小圆半径为r，大圆半径为R
则有：R=2r-1
两圆面积和为：π*r^2+π(2r-1)^2=65π
解得：r=4英尺（负根舍去）
则大圆半径R=7英尺。
2、一个正方形和一个长方形面积和为64平方厘米，长方形的宽比正方形边长2厘米，长方形的长比宽长2厘米。求长方形和正方形的尺寸。
设正方形边长为a，则长方形的宽为a+2，长方形的长为a+4。
则面积和为：a^2+(a+2)(a+4)=64
解得：a=4厘米（负根舍去）
则长方形的长和宽分别为8厘米和6厘米。
3、Ortegas有一个90棵树的苹果园，果树每行的棵数是总行数的两倍多3。求果树总行数和每行的棵数。
设总行数为x，则每行的棵数为2x+3
则总数量为：x*（2x+3）=90
解得：x=6
则每行的棵数为15棵。

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