I got the same answer as the example

Evaluate the discriminant of each equation. tell how many solutions each equation has and whether the solutions are real or imaginary. x^2 - 4x - 5 = 0

In a right triangle δabc, the length of leg ac = 5 ft and the hypotenuse ab = 13 ft. find: b the length of the angle bisector of angle ∠a.

Arectangle plot measure 20ft. by 30ft. a 3-ft.-wide sidewalk surrounds it.find the area of the sidewalk.