1、50,10
2、45,15,
3、一个解,30
(1)50-10 (2)15-45 (3) 30-30
1.x(60-x)=500
-X^2+60X-500=0
X^2-60X+500=0
(X-10)(X-50)=0
X=10 X=50
2.x(60-x)=675
-X^2+60X-675=0
X^2-60X+675=0
(x-15)(x-45)=0
X=15 X=45
3.x(60-x)=900
-X^2+60X-900=0
X^2-60X+900=0
(X-30)^2=0
X=30