The integer k is selected at random from the set of ten integers {0, 1, 2, ..., 9}. What is the probability that the equation x^2 + 3x + k = 0 has real roots?
For real roots the disciminat has to be positive
b2-4ac>0 3^2-4(1)(k) > 0
9-4k>0
4k > 9
k > 9/4 so from the list 0- 9 is ten numbers of which 3-9 will result in real roots 7/10
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