SOLUTION: Please help me solve graphing inequalities in 2 variables. In 2004, the median yearly family income was about $44,000 per year. Suppose the average annual rate of change since then

Algebra ->  Linear-equations -> SOLUTION: Please help me solve graphing inequalities in 2 variables. In 2004, the median yearly family income was about $44,000 per year. Suppose the average annual rate of change since then      Log On


   

Question 1002800: Please help me solve graphing inequalities in 2 variables. In 2004, the median yearly family income was about $44,000 per year. Suppose the average annual rate of change since then is $1240 per year. How can I write and graph an inequality for the annual family incomes y that are less than the median for x years after 2004.
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
if you let x = 0 to represent the year 2004, then your inequality will be:

y < 1240 * x + 44000.

you will graph y = 1240 + 44000.

you will make the line dashed to indicate that your inequality is less than and not less than or equal to.

if the line is dashed, then any values on the line are not valid.

only values of y below the line are valid.

you will shade the region that satisfies the inequality.

that region will be all values of y less than any values of y on the line.

for example, when x = 10, y = 56400 based on the equation y = 1240x + 44000.

when x = 10, all values of y < 56400 will satisfy the inequality.

y = 56400 will not satisfy the inequality because it is not less than 564000.

that's why the line is dashed.

a dashed line tells you that any value on the line does not satisfy the inequality.

if the inequality was <= (less than or equal), then a solid line would be used because values on the line would then be valid.

your graph will look like this.

$$$

here's a reference that tells you the same thing.

http://www.purplemath.com/modules/ineqgrph.htm