Maybe The 30% And 70% Is In The Other Triangle And You Do The Same Thing Thats What I Am Guessing Not 100% Sure About It Because I Have Not Learned This Yet! :P
Angle D is 80 degrees The lines on the triangles show that both the triangles are congruent (equal in length and value) to each other). A triangle is equal to 180 degrees. 30 + 70 is 100. 180- 100 equals 80. Therefore, because the triangles are congruent to each other, then both angle B and angle D must be 80 degrees
