Answer:
y = -3x + 7
Explanation:
Step 1: find the slope 
m = y2 - y1 / x2 - x1
Given two points 
( 2 , 1) ( 0 , 7)
x1 = 2
y1 = 1
x2 = 0
y2 = 7
m = 7 - 1 / 0 - 2
 = 6 / -2
 = -3
Step 2 : using the point slope equation 
y - y1 = m( x - x1)
( 0 ,7)
x1 = 0
y1 = 7
y - 7 = -3( x - 0)
Step3: using a slope intercept form equation 
y = mx + c
y - 7 = -3x + 0
y = -3x + 0 + 7
y = -3x + 7
The equation of the line in slope intercept form is 
y = -3x + 7