SOLUTION: Graph 2x+5y > or equal to 10

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Question 548285: Graph 2x+5y > or equal to 10
Answer by mathie123(224) About Me  (Show Source):
You can put this solution on YOUR website!
Let's first graph the line
2x%2B5y=10
We will put this into slope-intercept form to make this easier:
2x%2B5y=10
5y=10-2x
y=2-%282%2F5%29%2Ax
y=-%282%2F5%29%2Ax%2B2
So this line looks like
graph%28300%2C+300%2C+-10%2C+10%2C+-10%2C+10%2C+-%282%2F5%29%2Ax%2B2%29

Now, our graph is essentially broken up into two regions. We can take a point in each region and "test it". ((You can pick any points... because I like work to be easy... I will pick points on the x or y axis so I have a zero to deal with)
For the lower region I will use (0, 0)
so
2x%2B5y%3E=10
2%2A0%2B5%2A0%3E=10
0%3E=10
This is not true, so we cannot shade this region.

For the upper region I will use (0,3)
2x%2B5y%3E=10
2%2A0%2B5%2A3%3E=10
15%3E=10
This is true, so I can shade the upper region.
Since
2x%2B5y%3E=10
Has a = to 10, the line will be solid.... if however it was just >, the line would be dotted as the region would get really close to the line but would never touch the line.

Hopefully this helps, let me know if you are still unsure:)