The sales tax for an item was 29.70 and it cost 330 before tax. Find the sales tax rate. Write your answer as a percentage

The sum of each of the angles in a triangle always equals 180. We are given angles A and C so all we need to do is add them together and subtract from 180 to find the missing angle.

Angle C is 34
Angle A is 90 (that little box indicates 90)
34+90=124
180-124=56

Ange B is 56 degrees.

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