The point-slope form:
[tex]y-y_1=m(x-x_1)\\\\m=\dfrac{y_2-y_1}{x_2-x_1}[/tex]
We have the points (-8, -8) and (-7, 9). Substitute to the formula of a slope:
[tex]m=\dfrac{9-(-8)}{-7-(-8)}=\dfrac{17}{1}=17[/tex]
Put the coordinates of the point (-7, 9) and the value of slope to the point-slope formula:
[tex]y-9=17(x-(-7))\\\\\boxed{y-9=17(x+7)}[/tex]
