SOLUTION: For the equation x2 + 3x + j = 0, find all the values of j such that the equation has two real number solutions. Show your work.

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Question 701571: For the equation x2 + 3x + j = 0, find all the values of j such that the equation has two real number solutions. Show your work.
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
Assume you mean x%5E2%2B3%2Ax%2Bj=0. Either know what is the discriminant, or try filling in solution to quadratic equation.
x=%28-3%2B-sqrt%289-4%2Aj%29%29%2F2
Notice if you want only Real solutions, then the square root's radicand must be positive. 9-4%2Aj%3E=0. Only a simple matter to find j.
-4j>=-9
j<=(9/4) [multiplied both sides by -(1/4)]