(d)find the hcf of 21 and 84

If the slope of one line equals the slope of another line then ? a) the two lines are intersecting lines b) the two lines are perpendicular lines c) the two lines are parallel lines d) the two lines always have very steep slopes

Reflect the point (7,0) across the y-axis

What is the axis of symmetry of the function f(x)=-(x+ 9)(x-21)