Which coefficient matrix represents a system of linear equations that has a unique solution.

An arc subtends a central angle measuring 7pi/4 radians what fraction of the circumference is this arc?

At $1.32 million, they closed last month percent above what they paid in 2007." how much did they pay in 2007?

The figure below shows rectangle abcd and the triangle eca on a coordinate plane. which of the following expressions represents the perimeter of triangle of triangle eca in units