Answer:
104 degrees
Explanation:
First let's start by finding Angle DGC. Since Angle FGD and DGC are a linear pair, Angle DGC = 180-90 = 90 degrees.
Next we need to find GDC
Angles in a triangle add up to 180 degrees therefore...
Angle GDC + DCG + DGC = 180
Plug in the values we found into the equation
Angle GDC + 37 + 90 = 180
Angle GDC + 127 = 180
Angle GDC = 53
Therefore Angle ADC = 53 + 51 = 104 degrees
Since ABCD is a parallelogram, then opposite angles are equal therefore...
Angle B = 104 degrees