## Precalculus (6th Edition) Blitzer

$3$; $second$; $-2$; $third$.
Recalling the rules of row operations, we can complete the sentences as: We can obtain $0$ in the position shaded by a rectangle if we multiply the top row of numbers by $3$ and add these products to the $second$ row of numbers. We can obtain $0$ in the position shaded by an oval if we multiply the top row of numbers by $-2$ and add these products to the $third$ row of numbers.