What forms when a cold front overtakes a warm front?

The answer is occluded front

occluded front

Explanation:

The warm front is an air mass of the region found at the edge of the warm air mass and is typically located in the equatorial regions and they lie within the areas of the low density. And they develop in the areas of the same type of humidity and moisture conditions and being light and warmer air mass they are forced to go upwards along the upper parts of the colder air mass is the process that is called as the overrunning. Their boundaries remain about 1:200 and lifting is slow but consistent, the replacement of the warm air mass is taken by the cold front and is associated with the narrow bands of clouds and the precipitation. The resultant font is called as the occulant front.

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