Answer:
point slope: y-y1=m(x-x1)
m is slope. now we plug in numbers
y--9=1/2(x--7)
a negative times a negative us positive and a negative times a positive is negative
y+9=1/2(x+7)
now distribute 1/2
y+9=1/2x+7/2
now get y alone by using opposite operation to get 9 on the other side of the equal sign
y and nine are adding. the opposite of addition is subtraction
y+9-9=1/2x+7/2-9
y=1/2x+7/2-9
get 7/2 and 9 to have equal denominators
(7/2)-(9/1)
multiply 2 for numerator and denominator
(7/2)-((9÷1)×(2÷2))
7/2-18/2=-11/2
y=1/2x-11/2