Given the graph of a scatterplot and a trend line, explain how you would find the equation of the trend line.

first of all, the trend line will be in the form of y = mx + c. ( where m = gradient of a line and c = y-intercept. )

secondly, extend the trend line to touch the y-axis and then read the value of where the line intersects the y-axis. from this you'll get the value of c.

finally take two coordinates from the

trend line and use the gradient formula. this will be the answer for getting m.

a) y = -3x +2

b) y = 1/2x -6

these 2 can be combined into one equation.

-3x +2 = .5x -6

8 = 3.5x

x = 8 / 3.5 = 2.2857142857

y = -3 * (8 / 3.5) +2

y = (-24 / 3.5) + 2

y = -4.8571428571

step-by-step explanation: