选择适当方法解方程(1)(3x-2)²=5(3x-2) (2)2x²+3=7x (3)x²+2x=99
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![选择适当方法解方程(1)(3x-2)²=5(3x-2) (2)2x²+3=7x (3)x²+2x=99](/uploads/image/z/3761108-44-8.jpg?t=%E9%80%89%E6%8B%A9%E9%80%82%E5%BD%93%E6%96%B9%E6%B3%95%E8%A7%A3%E6%96%B9%E7%A8%8B%EF%BC%881%EF%BC%89%EF%BC%883x-2%29%26%23178%3B%3D5%283x-2%29+%282%292x%26%23178%3B%2B3%3D7x+%283%29x%26%23178%3B%2B2x%3D99)
选择适当方法解方程(1)(3x-2)²=5(3x-2) (2)2x²+3=7x (3)x²+2x=99
选择适当方法解方程
(1)(3x-2)²=5(3x-2) (2)2x²+3=7x (3)x²+2x=99
选择适当方法解方程(1)(3x-2)²=5(3x-2) (2)2x²+3=7x (3)x²+2x=99
解
(3x-2)²=5(3x-2)
(3x-2)²-5(3x-2)=0
(3x-2)[(3x-2)-5]=0
(3x-2)(3x-7)=0
x=2/3或x=7/3
2x²+3=7x
2x²-7x+3=0
(2x-1)(x-3)=0
x=1/2或x=3
x²+2x=99
x²+2x-99=0
(x-9)(x+11)=0
∴x=9或x=-11