Complete the point slope equation of line through (1,-1) and (5,2) use exact numbers
)=

(1,-1)(5,2)
slope = (2 - (-1) / (5 - 1) = 3/4

there will be 2 point slope answers for this..
y - y1 = m(x - x1)
slope(m) = 3/4
(1,-1)...x1 = 1 and y1 = -1
sub
y - (-1) = 3/4(x - 1)
y + 1 = 3/4(x - 1) <=== this is one of them

y - y1 = m(x - x1)
slope(m) = 3/4
(5,2)...x1 = 5 and y1 = 2
sub
y - 2 = 3/4(x - 5) <== here is the other one