One set of magnet with 10% discount would cost
(6.4)*(1-0.10) =
6.4*0.9 = 5.76
For two sets of magnets
5.76*2 =11.52
The slope of the line is calculated using
y2 - y1 / x2 - x1
Substituting the given values
-8 - 27 / 5 - 0 = -7
The rate of change or the slope is -7
And the initial value is the value of y when x is 0. From the first coordinates, the initial value is 27.
It would be: 2 × x + 4 + 2× x
= 2x + 4 + 2x
= 4x + 4
In short, Your Final Answer is 4x+4
Hope this helps!