Answer:
y = 4x + 5
Explanation:
The equation of a straight line line is;
y = mx + b
where m is the slope and b is the y-intercept
We start by calculating the slope value by using the slope equation
m = (y2-y1)/(x2-x1)
m = (9+ 7)/(1+ 3) = 16/4 = 4
So we have the equation as;
y = 4x + b
to get the value of b, we substitute the coordinates of any of the two points
let us use (1,9)
9 = 4(1) + b
b = 9-4
b = 5
so, we have the equation of the line as;
y = 4x + 5