Step-by-step explanation:
the typical line equation is
y = ax + b
a is the slope. it is the ratio of "y coordinate change / x coordinate change".
b is the y-intercept (the y value when x = 0) indicating the point, where the line crosses the y-axis.
going from one to the other point
x changes by +8 (from -6 to 2).
y changes by +4 (from 3 to 7).
so, the slope a is +4/+8 = 1/2.
the semi-finished equation is
y = 1/2 x + b
for b we use one of the points in the equation and since for b. let's go for (2, 7) :
7 = 1/2 × 2 + b = 1 + b
6 = b
so, the full equation is
y = 1/2 x + 6