The total cost of a $2,099 couch including the 6.5% sales tax is $ 2235.435
<u>Solution:</u>
Given that,
cost of couch = $ 2099
Sales tax = 6.5%
<em><u>Finding the total cost of couch with sales tax:</u></em>
Total cost of couch = selling price of couch + sales tax on the selling price of couch
Plugging in values we get,
<em>Total cost of couch = $ 2,099 + 6.5% sales tax on $ 2099</em>

Taking "2099" as common term, we get,

On solving brackets,

Hence, the total cost of the couch is found as $ 2235.435
To have infinitely many solutions they must describe the same line. So any multiple or fraction of the reference line would indeed describe the same line, and thus "intersect" at each and every of an infinite number of points.
2(x+y=4)
2x+2y=8 (is the same line as x+y=4)