Can someone me figure out the answer?

y = -2x +15

Step-by-step explanation:

The point-slope form of the equation for a line through (h, k) with slope m is ...

... y - k = m(x - h)

For your point (h, k) = (5, 5) and slope m = -2, the equation in point-slope form is ...

... y - 5 = -2(x - 5)

Simplifying, we get

... y - 5 = -2x +10

Adding 5 puts the equation into slope-intercept form, as you want.

... y = -2x +15