values of x

Question

Select he value of x that are solutions to the inequality

 

0>x^2+5x-2

 

1. xE (-5-33 squared/2,-5+33 squared/2)

 

2. xE [-5-33 squared/2,-5+33 squared/2]

 

3. xE (- infinite sign, -5-33 squared/2)∪(-5+33 squared/2, infinite sign)

 

4. xE( - infinite sign,-5-33 squared/2]∪[-5+33 squared/2, infinite sign)

 

I came up with the first answer. Did I do this correctly or can you explain how to do this problem.

Answer 1

Your solutions are

 

          x₁ = (-5 +√(33))/2    and x₂ = (-5-√(33))/2

Answer 2

Hi Katie,

 

Yeah, looks like you did it correctly.  The way you wrote your answer choices was confusing, though, so it's hard to tell.  I'd write them like this:

 

1. xE ((-5-sqrt(33)/2,(-5+sqrt(33))/2)

 

2. xE [(-5-sqrt(33)/2,(-5+sqrt(33))/2]

3. xE (- infinite sign, (-5- sqrt(33))/2)∪((-5+sqrt(33))/2, infinite sign)

 

4. xE (- infinite sign, (-5- sqrt(33))/2]∪[(-5+sqrt(33))/2, infinite sign)


Notice that the 5 and the sqrt(33) is grouped with an extra pair of parentheses... you need the parentheses to show that it's not just sqrt(33) being divided by 2, but the 5 as well.

 

Anyway, good work, let us know if further clarifications are needed!