a parallelogram has 4 angles each adding up to 360°. two pairs of angles will be the same so angle A and angle B. Angle A=B-55 and 2A+2B=360 substitute A
2(B-55)+2B=360
distributive property: 2B-110+2B=360
add over 110 and combine like terms: 4B=450
divide by 4: B=112.5
substitute B into A=B-55: A=112.5-55=57.5
the smaller angle is 57.5°