Can EAs draw trendlines like indicators?

 
Very basic question but I still haven't learned this. Can EAs draw trend lines on the chart? I want my EA to draw the GBPUSD bid prices on my EURUSD chart. If its possible please point me in the right direction. I need to know which commands I'll need to study and if there are script templates out there I could reverse engineer. Thanks guys!! =)
 
Have a look at ObjectCreate() which allows you to draw lines, symbols, text etc on the main bar chart.
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