I have a question on my homework I don't really understand, and I was wondering if anyone could help me.

The question is:

Show that the two planes are neither coincident, parallel, nor distinct. Identify, geometrically, how the planes intersect and determine the angle between the two planes to the nearest degree.

x + 2y - 4z + 7 = 0

2x - 2y - 5z + 10 = 0

If anyone could help me out I'd really appreciate it! Thanks in advance!