Find a1 for the geometric series described.
Sn=-342, an=-512, r=-2

Plz determine whether the polynomial is a difference of squares and if it is, factor it. y2 – 196 is a difference of squares: (y + 14)2 is a difference of squares: (y – 14)2 is a difference of squares: (y + 14)(y – 14) is not a difference of squares

If a 36 inch yardstick casts a 21 foot shadow, how tall is a building whose shadow is 168 feet? what is the scale factor

Iknow its nothing to do with education, but what type of thing should i wrote here? ? : ) its for mcdonald's btw.