How do you factor $y^2 + 0.2y - 0.15$ ?

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Answer 1 · 2016-08-28T15:54:07

$y^2+0.2y-0.15=(y+0.5)(y-0.3)$

Note that $5*3 = 15$ and $5-3 = 2$ . We use this later...

If we let $x=0.1$ then:

$y^2+0.2y-0.15$

$=y^2+2xy-15x^2$

$=(y+5x)(y-3x)$

$=(y+0.5)(y-0.3)$

How do you factor y^2 + 0.2y - 0.15y^2 + 0.2y - 0.15?