While working in a study group Joan asks a question and is given an incorrect answer by Dave, another memberthe whole group accepts the answer as true and writes it down. Although another member of the group has questions about the answer the entire group simply agrees with Dave's answer without checking it and ultimately they all get the question wrong on the FRO (14.5 Points)

if triangle abc is congruent to triangle def, their interior angles are congruent, because congruent parts of congruent triangles are congruent (cpctc).

that means ∠d is congruent to ∠a; ∠d is equal to 8x - 2.

interior angles of all triangles add to equal 180 degrees, so you can set the sum of these interior angle values equal to 180 and solve for x.

180 = (8x - 2) + 22 + 72

180 = 8x - 2 + 22 + 72

180 = 8x + 92

88 = 8x

11 = x

x = 11