Write and equation for f6 3 f9 15?

Answer 1

f(6) = 3 This gives us the point (x1, y1) = (6, 3), and

f(9) = 15, gives us the point (x2, y2) = (9, 15).

Since we have two points, we can write the point slope intercept form of the equation of the line passing through these two points. To do this we need to find the slope m of the line. So,

slope = m = (y2 - y1)/(x2 - x1) = (15 - 3)/(9 - 6) = 12/3 = 4

(y - y1) = m(x - x1) the point slope intercept form

(y - 3) = 4(x - 6)

y - 3 = 4x - 24 add 3 to both sides

y = 4x - 3 subtract y to both sides

0 = 4x - y -3 or

4x - y -3 = 0