Option b: 10 in, 18.5 in, 31.5 in.
Explanation:
The three sides of a triangle are 
and 
The perimeter of the triangle is 
.
Since, Perimeter = all sides of the triangle
Let us add all the three sides to determine the length of each side.
Substituting the value of Perimeter and simplifying, we get,
Substituting 
in the three sides of the triangle and , we get,
Thus, the lengths of each side are 10 in, 18.5 in, 31.5 in.
B: a reflection across the x-axis followed by a translation 4 units right.
Comparing the points to their mapped images compares A to E, B to F, C to G, and D to H. In each point, the y-coordinate switches signs and the x-coordinate is subtracted by 4.
Reflections across the x-axis will switch the sign of the y-coordinate, and reflections across the y-axis will switch the sign of the x-coordinate. Since the y-coordinates are the ones whose sign changed, the points must have been reflected across the x-axis.
Translations to the left will cause the x-coordinate to increase, and translations to the right will case the x-coordinate to decrease. Since the x-coordinate of every point was subtracted, this means that the translation must have been to the right.
