180/(x-15)-180/x=2详细的步骤
180/(x-15)-180/x=2
详细的步骤
180/(x-15)-180/x=2
解:方程两边同时是、乘以x(x-15)得
180x-180x+2700=2x(x-15)
化简得
x^2-15x-1350=0
由十字相乘法得
(x-45)(x+30)=0
解得x1=-30,x2=45
x1=-30,x2=45
180/(x-15)-180/x=2
(180/(x-15)-180/x)/2=2/2
90/(x-15)-90/x=1
90x-90(x-15)=x(x-15)
x*x-15x-1350=0
(x-45)(x+30)=0
∴x1=-30
x2=45
两边同时是、乘以x(x-15)
180[x-x+15]=2x(x-15)
x^2-15x-1350=0
(x-45)(x+30)=0
x=45 或 x=-30
2X(X-15)=2700
X(X-15)=1350
公式:(A-B)平方=A平方+B平方-2AB
X=45
180{15/(x-15)x}=2
90*15=x(x-15)
x(x-15)-90*15=0
(x+30)(x-45)=0
解的:x=-30或 x=45
方程化简为
90/(x-15)-90/x=1
90x-90(x-15)=x(x-15)
x^2-15x-1350=0
解的x1=-30,x2=45
180/(X-15)-180/X=2两边约去2,即90/(X-15)-90/X=1,
通分移项后:90X-90(X-15)=X(X-15)
去括号合并同类项有:X^2-15X-1350=0
左边分解因式后有:(X-45)(X+30)=0
解得:X=45或-30。