In terms of pi means to include pi in your answer. In other words, don't use 3.14 or 22/7 for pi.
The measurement of <ABC is 50 degrees

so our slope is undefined, that means a vertical line, check the picture below
The Correct Answer Is f(x)=2.5x+5
This In Expression Form Is:
3r + 4t.
The Reason Why Is Because:
When You Triple r, That Is 3r, And When You Quadruple t, It becomes 4t. And Plus Means to Add. So, This Becomes 3r + 4t
I Hope this Helps!