Question

Answer should be y + 4x = 13 but not sure how to get to this? Where am I going wrong?

Find the equation of the line joining points (1,9) and (3,1)
m=y2-y1/x2-1= 1-9/3-1=-8/2=-4
m= -4, a = 3, b= 1
y-b= m(x-a)
y-1=-4(x-3)
y-1=-4x+12
y= -4x + 11?

Answer 1

To find the equation of the line joining two points, (1,9) and (3,1), calculate the slope and substitute one of the points into the slope-intercept form of a linear equation.

Step-by-step explanation:

The equation of the line joining points (1,9) and (3,1) can be found using the slope-intercept form of a linear equation, which is y = mx + b. First, calculate the slope (m) using the formula (y2 - y1) / (x2 - x1). In this case, the slope is (1 - 9) / (3 - 1) = -8/2 = -4. Next, choose one of the given points to substitute and solve for the y-intercept (b). Using (1,9), substitute x = 1 and y = 9 into the equation and solve for b: 9 = -4(1) + b, so b = 9 + 4 = 13. Finally, substitute the values of m and b into the slope-intercept form to get the equation of the line: y = -4x + 13.