How many degrees do the parallels divide the earth into?

Each meridian forms half of a great circle, assuming a spherical earth. meridians intersect lines of latitude (parallels) at right angles. the spherical earth is divided into  360 degrees   east-west. lines of longitude range from 0° to  180° to the east and from 0° to -180 ° to the west of the prime meridian.

2. x2 + 8x + 12 = 0 to prove: x = -6 or x = -2