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Question 1186822:
Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
Write the quadratic equation whose roots are −3 and − 4, and whose leading coefficient is 4. (Use the letter x to represent the variable.)
If the leading coefficient were 1 and not 4, the quadratic equation would be:

x%5E2%22%22-%22%22%28matrix%283%2C1%2CSUM%2COF%2CROOTS%29%29x%22%22%2B%22%22%28matrix%283%2C1%2CPRODUCT%2COF%2CROOTS%29%29%22%22=%22%220 

So we begin by finding that:

SUM OF ROOTS = (-3) + (-4) = -7

PRODUCT OF ROOTS (-3)(-4) = 12

So with leading coefficient 1, the answer would be 

x%5E2%22%22-%22%22%28-7%29x%22%22%2B%22%22%2812%29%22%22=%22%220

simplify

x%5E2%22%22%2B%22%227x%22%22%2B%22%2212%22%22=%22%220 

To make it have leading coefficient of 4, simply multiply through by 4:

4x%5E2%22%22%2B%22%2228x%22%22%2B%22%2248%22%22=%22%220

Edwin