Answer:
Add the two angles: 43° + 47° = 90°.
Step-by-step explanation:
A right triangle has an angle that equals 90°. Complementary angles equal 90°. Therefore, if you add these two angles, you will know whether or not △ABC is a right triangle. Triangle △ABC is broken up into two angles, m∠ABD and m∠DBC. When the measures m∠ABD and m∠DBC are added together, they equal 90°, and thus, form a complementary angle.
Hope this helps,
♥<em>A.W.E.</em><u><em>S.W.A.N.</em></u>♥
