The slope of a line is constant because the acceleration is equal to zero.
The slope of a line is always just (y2-y1)/(x2-x1), so in this case:
m=(-7-6)/(4--6)
m=-13/10
m=-1.3
X could either be 4 or 5, depending on which x the question asks. If you have to chose one answer go with 5 because it's associated with the y.
When you are multiplying and have like bases, then you add the exponents.
2+3=5
3^5
the answer would be y = 2x + 1