SOLUTION: If the roots of ax^2 + bx + c are 3/2 and -5/4 and a, b, c are whole numbers, what are the valies of a, b, and c?

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Question 1089718: If the roots of ax^2 + bx + c are 3/2 and -5/4 and a, b, c are whole numbers, what are the valies of a, b, and c?
Found 2 solutions by josmiceli, ikleyn:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+%28+x+-+3%2F2+%29%2A%28+x+-%28-5%2F4%29+%29+=+0+
+x%5E2+-+%283%2F2%29%2Ax+%2B+%285%2F4%29%2Ax+-+%285%2F4%29%2A%283%2F2%29+=+0+
+x%5E2+-+%281%2F4%29%2Ax+-+15%2F8+=+0+
+x%5E2+-+%282%2F8%29%2Ax+-+15%2F8+=+0+
+8x%5E2+-2x+-+15+=+0+
+a=8+
+b=+-2+
+c+=+-15+
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check:
use quadratic formula to verify

Answer by ikleyn(52778) About Me  (Show Source):
You can put this solution on YOUR website!
.
I agree with the solution by @josmiceli,  and only want to add that 


together with the triple ((a,b,c) = (8,-2,-15)  any other triple which is multiple to this one, is also the solution.


For example, triples (a,b,c) = (16,-4,-30)  and (-8,2,15)  also are the solutions.