This is number 8. the second person got number 9
6x^2 + x - 15 = 6x^2 - 9x + 10x - 15 = 3x(2x - 3) + 5(2x - 3) = (3x + 5)(2x - 3)
Therefore, the other factor is 3x + 5.
The length of the diagonal of the square is the square root of 32 which equals approximately 5.6569.
The length from the corner to the center of the square is half of the diagonal which is 2.8284. I hope this helps!