3d+ 3s = $21 because they bought three drinks and three snacks
Answer:
C. 150
Step-by-step explanation:
It's right on Plato.
The point-slope form:

- given point
- given slope
The standard form:

<em>use distributive property</em>
<em>add
to both sides</em>
<em>subtract
from both sides</em>
<em>change the signs</em>
