Factoring a PolynomialDate: 04/06/97 at 20:05:18 From: amanda butts Subject: Factoring a Polynomial How do I solve 3y^2+12y = 0 ? Date: 04/07/97 at 20:15:01 From: Doctor Mike Subject: Re: Factoring a Polynomial Dear Amanda, You have probably seen the Distributive Law. One of several versions of it is (A + B)*C = A*C + B*C. You can apply this to the left side of your equation, because y^2 is really y times y. It becomes : (3y + 12)*y = 0 We have not changed the equation much; just factored the left side. Now what? In order for y to be a solution to this equation, one of the 2 things multiplied on the left must be equal to zero. So, that means y=0 will work. But how do you choose y so that 3y+12 is zero? This is a simpler kind of equation that you have seen before. If you solve that equation for y, that will give you the other solution. Hint: the second solution is a negative number. Good luck. I hope this helps. -Doctor Mike, The Math Forum Check out our web site! http://mathforum.org/dr.math/ |
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