Originally Posted by: wmlkb8310Guitar tricks teaches songs and scales but how do you know what scales to use? Do you play the scale for the key you are in or the chord being played? When do you use minor pentatonics?

Great questions! In general, yes, you play the scale for the key you are in. In some cases all the chords are in the same key & this neatly follows the idea of staying in key. In other cases you'll have to alter the scale or even change keys & play a different scale in order to follow the chords.

The relationship between scales & chords is covered in depth in the courses. For example, in Guitar Fundamentals 2:

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Anders does a great job of explaining it as it is used in the genres of blues & rock in the Blues & Rock Style Courses.

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If you've already gone through the courses, there is also this series on improvisation that goes more in depth into the topic of how to play in key & balance that with following the chords.

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As to how to incorporate the pentatonic scales, have a look at this series of tutorials!

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Hope this helps! Ask more if necessary & best of success!