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[IMAGE ATTACHED]
I don’t understand this please help.

[IMAGE ATTACHED] I don’t understand this please help.-example-1
User Fanl
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1 Answer

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You are given two angles: 55 degrees and 90 degrees (the right angle)
You know that the whole angle should be 180 since a straight line has an angle of 180 degrees.
55+90= 145
180-145=35
Set (9r-1)° equal to 35 and you should get r=4
User Emerion
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