Ответы и объяснения

2014-03-16T16:32:19+04:00
(5 - х)² = 3х(5-х)
25 +х² -10х -15х +3х² = 0
4х² - 25х +25 =0
D = 525 - 400 = 125 = 5√5
х₁ = (25 -5√5)/8
х₂ = (25+5√5)/8
2014-03-16T16:44:33+04:00
(5-x)²=3x(5-x)
5²-10x+x²=15x-3x²
25-10x+-15x+3x²=0
4x²-25x+25=0
D=(-25)²-4·4·25=625-400=√225=15
x1=25-15/2·4=10/8=1,25
x2=25+15/2·4=40/8=5