why the columns of an LaTeX: m\times n matrix can never span LaTeX: \mathbb{R}^m if there are more rows than columns

Scrub a dub toothbrushes are $4.00 each. there is a 10% discount, but there is also a 6% sales tax after the discount is applied. what is the new price after tax? round to the nearest penny

Solve the equation -9p - 17 =10 a -3 b. 16 c. 18 d -16

1. find the area of the unshaded square 2. find the area of the large square 3. what is the area of the frame represented by the shaded region show