Formula for slope: 
y₂: 6
y₁: 8
x₂: 1
x₁: -2
Plug them into the slope equation:

--> 
---> 
The slope is
.
Answer:
Shown below
Step-by-step explanation:
I believe that the number machine would look like this:
number of hours x (£15) + (£25)

Multiplication by 10ⁿ → move decimal n places to the right.
Multiplication by 10⁻ⁿ → move decimal n places to the left.
For n ∈ N
Answer is C. HMG and LMK
see attached picture to explain
Vertical angles are congruent and opposite of each other where two lines cross