Question

Slope -1 passes through (7,2)

Answer 1

Y = mx + b
slope(m) = -1
(7,2)...x = 7 and y = 2
now we sub and find b, the y int
2 = -1(7) + b
2 = -7 + b
2 + 7 = b
9 = b

so ur equation of this line is : y = -1x + 9.....can also be written as :
y = -x + 9....or if u need it in standard form, it is : x + y = 9

Answer 2

Assuming you're looking for the equation of this line...

-1 = (y - 2) / (x -7)

-1 (x - 7) = (y - 2)

-x + 7 = y - 2

-x + 7 + 2 = y

-x + 9 = y

y = -x + 9

Hope this helps!