How do you solve this system of equations: 5x - 2y < - 6 and x + 2y \geq - 6?

1 Answer
Dec 2, 2017

See picture and explanation below.

Explanation:

We can solve a system of inequalities by graphing the inequalities and seeing where they both are true.

First we have to convert both inequalities to slope-intercept form, y=mx=b.

First inequality:

5x-2y<-6

\implies -2y<-5x-6

\implies \underbrace{y>\frac{5}{2}x+3}_{\text{flip the inequality sign}}

Now the second inequality:

x+2y\geq -6

\implies 2y\geq -x-6

\implies y\geq -\frac{1}{2}x-3

Since we have both inequalities in slope intercept form, we can graph both of them:

Deamos

The area shaded purple is the solution.