A2=-3 a3=-2 q=a3/a2=2/3 a1=a2/q=-3*3/2=-9/2
1)36-20x+7x=11-16x-2
36-13x=9-16x
3x=-27
X=-9
2)9x-36+21x=30x-35+1
30x-36=30x-34
?
8x+10-15x=4-60x-18
-7x+10=-14-60x
53x=-24
X=-24/53
-8х-32х+6х+24=0
-34х=-24
х=12/17
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1) (2x-5)(3x+4)=6x^2+8x-15x-20=6x^2-7x-20
2) (x-3y)(2y-5x)=2xy-5x^2-6y^2+15xy=17xy-5x^2-6y^2
3) a(a-5)-(a-2)(a-3)=a^2-5a-a^2+3a+2a-6=-6
4) (2a+1)(4a^2-2a+1)=8a^3+1