Is this the relationship shown by the data linear? if so model the data with an equation. (1,-4) (7,-7) (13,-10) (19,-13)

(1,-4)(7,-7)
slope = (-7 - (-4) / (7 - 1) = -3/6 = -1/2
(13,-10)(7,-7)
slope = (-7 - (-10) / (7 - 13) = -3/6 = -1/2
(13,-10)(19,-13)
slope = (-13 - (-10) / (19 - 13) = -3/6 = -1/2

yes...this is linear
y = mx + b
slope(m) = -1/2
use any of ur points...(1,-4)...x = 1 and y = -4
now sub and find b, ur y int
-4 = -1/2(1) + b
-4 = -1/2 + b
-4 + 1/2 = b
-8/2 + 1/2 = b
-7/2 = b

so ur equation is : y = -1/2x - 7/2or x + 2y = -7

Iam pretty sure its a sorry if im wrong