Does it make sense that sin(-0)= -sin0

Kylie explained that (-4x+9)^2 will result in a difference of squares because (-4x+9)^2 (-4x+9)^2 =(-4x)^2+(9)^2=16x^2+81

Find the equation of the line with slope =8 and passing through (6,53) write your equation in the form y=mx+b

Solve the equation by completing the square. x^2+2x=17