The equation of a line in Slope-Intercept form, is:

Where "m" is the slope of the line and "b" is the y-intercept.
By definition:
- The slopes of parallel lines are equal and the y-intercepts are different.
- The slopes of perpendicular lines are opposite reciprocals.
For this case you need to rewrite the equations given in the exercise in Slope-Intercept form by solving for "y".
- Line #1:

You can identify that:

- Line #2:

You can identify that:

Therefore, since:

You can conclude that: The graphs of the equation are parallel.
Using the information provided, you would do 17/.85 to find the total amount. Subtract that quotient from 17 and you will get how much your friend spent.
Answer:
x = 23 degrees
Step-by-step explanation:
Supplementary angles add up to 180 degrees. Thus, 3x - 17 degrees plus al 5x + 21 deg must equal 180 degrees.
Combining like terms, we get 8x - 4 = 180, or 8x = 184.
Dividing both sides by 8 yields x = 184/8 = 23 = x (measured in degrees)
This has to do with ratios. If the current width is 8 inches and he wants to have it 35in, you must multiply the length by the same amount to keep it proportional.
If there are 2 office rooms, there are 6 rooms that aren't office rooms. So the percentage of non-office rooms can be expressed as:
# of non-office rooms/total rooms
or
6/8
In percentage, this is 75%
Hope this helps!