This ones beyond me!! Make x the subject: y=(x+4)(x+3) if anyone can explain this one to me i would be forever grateful
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Originally Posted by chrill911 This ones beyond me!! Make x the subject: y=(x+4)(x+3) if anyone can explain this one to me i would be forever grateful Good question! $\displaystyle y=(x+4)(x+3)\Rightarrow y=x^2+7x+12$ $\displaystyle x^2+7x+12-y=0$ Now, use the quadratic formula... $\displaystyle x=\frac{-7 \pm \sqrt{49-4(12-y)}}{2}$ $\displaystyle x=\frac{-7 \pm \sqrt{1+4y}}{2}$
Cheers for that!!! I gotta admit i dont fully understand the quadratic formula, but it's a step in the right direction!! Time to hit the books and do some more research..... Thanks a lot
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