1) 9ху+15х-6у+3=0
2) (a-b)(a-b+3)
3) Два решения
v=0
и
v=2/5
4(2а+1)²-(3а)²=(2(2а+1)-3а)) *(2(2а+1)+3а))=(4а+2-3а)(4а+2+3а)=(а+2)(5а+2)
X²+8x-209=0;.
D=b²-4ac=8²-4*1*(-209)=900=√900=30.
x1=-b+√D/2a=-8+30/2*1=14;;;.
x2=-b-√D/2a=-8-30/2*1=19..
<span>5х-2х=1,6+0.8
3х=2.4
х=2.4:3
х=0.8
б)4-4х+12=4х-20
8х=20-12-4
-8х=4
х=4:(-8)
х=-0.5
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