Compute the slope of the line through (-2, -9) and (-4, -17):
[tex]\dfrac{-9-(-17)}{-2-(-4)}=\dfrac82=4[/tex]
Any line perpendicular to this line will have slope -1/4. The one that passes through (0, 10) satisifes
[tex]y-10=-\dfrac14(x-0)\implies\boxed{y=10-\dfrac x4}[/tex]
