Simplify the following expression:
50x+30x+18x·5x-3x
=50x·5x+50x·-3x+30x·5x+30x·-3x+18x·5x+18x·-3x
=250x-150x+150x-90x+90x-54x
=250x-54x
Properties of Exponents:
am·an=am+n
aman=am-n
amn=am·n
ab-n=ban
a0=1
250x-54x