SOLUTION: Solve the following inequality. x2 + 8x + 15 > 0 A. (-∞, -5) or (-3, ∞) B. (-3, ∞) C. (-∞, -5) D. (-5, -3)

Algebra ->  Inequalities -> SOLUTION: Solve the following inequality. x2 + 8x + 15 > 0 A. (-∞, -5) or (-3, ∞) B. (-3, ∞) C. (-∞, -5) D. (-5, -3)       Log On


   

Question 444860: Solve the following inequality.
x2 + 8x + 15 > 0
A. (-∞, -5) or (-3, ∞)
B. (-3, ∞)
C. (-∞, -5)
D. (-5, -3)


Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2+%2B+8x+%2B+15+%3E+0+
x%5E2+%2B+3x%2B+5x+%2B+15+%3E+0+
%28x%5E2+%2B+3x%29%2B+%285x+%2B+15%29+%3E+0+
x%28x+%2B+3%29%2B+5%28x+%2B+3%29+%3E+0+
%28x%2B+5%29%28x+%2B+3%29+%3E+0+
solutions:
%28x%2B+5%29+%3E+0+...=>.....x%3E-5
%28x%2B+3%29+%3E+0+...=>.....x%3E-3
+graph%28+500%2C+500%2C+-10%2C+5%2C+-10%2C+10%2C+x%5E2+%2B+3x%2B+5x+%2B+15%29+
as you can see from the graph, parabola is above x-axis in this interval:
A. (-∞, -5) or (-3, ∞)