Y=-2/11x-5/11 is the slope intercept form
80% of 20 is 80/100 x 20 = 16
So, kelly has used 16 stamps, and has 4 left
we know that
If two lines are perpendicular, then the product o their slopes is equal to minus one
so
Step 1
<u>Find the slope of the given line</u>
we have
------->
This line is parallel to the y-axis
so
the perpendicular will be parallel to the x-axis
Step 2
The equation of the line perpendicular to the given line is the y-coordinate of the given point
Point
the equation is
therefore
<u>the answer is</u>
see the attached figure to better understand the problem
Since Doug’s brother has double the amount of Doug we can just multiply the amount Doug has by 2.
$3,215*2 = $6,430