解一元二次方程.5(X-3)²=X²-9 END
问题描述：
解一元二次方程.
5(X-3)²=X²-9 END
答
5(X-3)²=X²-9
5(X-3)²=(X-3)(X+3)
5(X-3)²-(X-3)(X+3)=0
(X-3)[5(X-3)-(X+3)]=0
(X-3)(5X-15-X-3)=0
(X-3)(4X-18)=0
(X-3)(2X-9)=0
X=3或X=9/2
答
5(X-3)²=5X2-30X+45=X2-9
移项得 4X2-30X+54=2(2X-9)(X-3)=0
故X=3或x=9/2
以上便是解题步骤，希望你能采纳！！！
答
5(X²-6X+9)=X²-9
5X²-30X+45=X²-9
4X²-30X+54=0
2X²-15X+27=O
(X-3)(2X-9)=0
X=3 X=2/9