Can I run my 4 interior speakers off a 2channel kenwood amp I have?2 front doors to 1ch and 2rear deck to 1ch?

Have a kenwood kac-7205 and dont wana buy another amp if I dont have to.. Want to run my 2fronts (Alpine Type S 50watt Rms 150peak i believe not totaly sure) and 2rear deck (Memphis Pr-692 60watts Rms 120peak) if I remember right the kenwood puts out 170watts per channel at 4ohms and 500watts at 4ohm bridged, niw I figured half of 170watts wuld be 85watts so figured both the alpine and memphis culd handle 85watts a piece seeing that im not over the peak power or wuld running 2speakers in 1channel not break the 170watts in half like would I end up with an uneven amount? Is it even possible? Culd I damage my speakers? PLEASE HELP with any info/links if possible Thanx so much in advance to whoever can help me!