puts "Enter Number of Points"
n=gets.chomp
n=n.to_i
sum_x=0
sum_y=0
sum_xx=0
sum_xy=0
i=0
while i<n
i=i+1
puts "For Point "+i.to_s
puts "Enter x"
x=gets.chomp
x=x.to_f
puts "Enter y"
y=gets.chomp
y=y.to_f
sum_x=sum_x+x
sum_y=sum_y+y
xx=x**2
xy=x*y
sum_xx=sum_xx+xx
sum_xy=sum_xy+xy
end

a=(-sum_x*sum_xy+sum_xx*sum_y)/(n*sum_xx-sum_x*sum_x)
b=(-sum_x*sum_y+n*sum_xy)/(n*sum_xx-sum_x*sum_x)
puts "The regression line is Y="+b.to_s+"X+"+a.to_s