# How do you solve #4+4p-5p^2>=0#?

##### 1 Answer

Aug 3, 2016

[p1 , p2]

#### Explanation:

Bring the quadratic inequality to standard form:

Since a< 0, the parabola opens downward. Between the 2 x-intercepts, f(p) >= 0, as a part of the parabola stays over the x-axis.

Find the 2 x-intercepts (real roots) by the new quadratic formula in graphic form (Socratic Search):

There are 2 x-intercepts:

Answer by closed interval: [p1 , p2]. The 2 end points p1 and p2 are included in the solution set.

Graph:

------------------------p1 === 0 ============ p2 ---------------------------