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2010-04-08T22:14:17+02:00
(x-3)(5-x)=(2-x)(x-4)
5x-x²-15+3x=2x-8-x²+4x
8x-x²-6x+x²=-8+15
2x=7
x=3,5


(x-3)(x+3)+10=x²-4+x
x²-9+10=x²-4+x
x²-x²-x=-4-1
-x=-5
x=5
2010-04-08T22:16:13+02:00
1.
(x-3)(5-x)=(2-x)(x-4)
5x - x² - 15 + 3x = 2x - 8 -x² + 4x
5x + 3x - 2x - 4x - x² + x²= -8 + 15
2x= 7 /:2
x=3,5

2.
(x-3)(x+3) + 10= x² - 4 + x
x² - 9 + 10 = x² - 4 + x
1= - 4 + x
1 + 4 = x
5 = x
x = 5 :)