Answer:
Equation of a line, y = mx+c
Slope (m)= (Y2-Y1)/(X2-X1), let Y2=7, Y1=3 , X2=2 and X1=1
m=(7-3)/(2-1)
= 4/1
= 4
Picking any value of y and its corresponding x including m, put them into the equation of the line
y=mx+c
3 =4(1)+c
3=4+c
3-4=c
-1=c
y=mx+c
y=4x+(-1)
y=4x-1
