Question

вот блинб, помогите.

Answer 1

$-8x^2-6x+5=0;\\8x^2+6x-5=0;\\D=6^2-4\cdot8\cdot(-5)=36+160=196;\\\sqrt{D} =\sqrt{196} =14\Rightarrow x_{1;2} =\displaystyle\frac{-6\pm14}{16} =-1,25;~0,5.$

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$16x^2-8x+1=0;\\(4x-1)^2=0;\\4x-1=0;\\4x=1;\\x=1:4=0,25.$

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$49x^2+14x+1=0;\\(7x+1)^2=0;\\7x+1=0;\\7x=-1;\\x=-\dfrac{1}{7} .$

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