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ex30:
(2x+3)(x-5)=2x(x-2)
2x²-10x+3x-15=2x²-4x
-3x-15=0
x=-15/3
droopette
(2x+3)(x-5)=2x(x-2)
2x²-10x+3x-15 = 2x²-4x
2x²-2x²-10x+3x+4x=15
-3x=15
x= -5

(2x-9)(8x-1)=(4x+3)²
16x²-2x-72x+9=16x²+24x+9
16x²-16x²-2x-72x-24x=9-9
-98x=0
x=0




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