What is the answer to 7 or 8???

7. parallel:  k = 3

   perpendicular:  k = -4/3

8. $1300

Step-by-step explanation:

7.

Rewrite each equation as the slope-intercept form of a linear equation:

y = mx + b (where m is the slope and b is the y-intercept)

  8y = 12x + 6

⇒

   4y = k(2x + 10)

⇒ 4y = 2kx + 10k

⇒

If the graphs are parallel their slopes will be the same.

If the graphs are perpendicular then the product of their slopes will be -1.

8. Create a linear equation, where x is the number of coffee mugs and y is the total cost (in dollars).

Choose 2 ordered pairs from the table:  (10, 110) and (20, 195)

Let = (10, 110)

Let = (20, 195)

Use the slope formula to find the slope m:

Now use the point-slope form of linear equation:

Substitute x = 150 into the equation and solve for y:

Therefore, the total cost of ordereing 150 mugs is $1300