What is the slope of a line that is perpendicular to y=1/2x+9 that passes through (-7,-4)

Hi there!

To find the perpendicular slope you need to flip the fraction and change the sign. So 1/2=2/1 and tge original slope was positive, so the slope is -2. Now you sub in the point (-7,-4) in for x and y in the formula y=mx+b and solve for b (sub in 2 for m as well)
Y=mx+b
-4=-2*-7+b
-4=14+b
-4-14=b
B=-18
The equation is y=-2x-18

Hope this helps!