The answer is b I’m pretty sure
Angle ADB is a right angle, which is given.
The measure of ADB is 90 degrees by definition of right angle.
The two angles are a linear pair (aka they're supplementary) by definition of linear pair (they're formed by two intersecting lines).
The measure of BDC is 90 because BDC + ADB = 180 (definition of linear pair), and ADB = 90 (given).
BDC = ADB because 90 = 90
Overall, the two triangles are congruent by SAS.
Answer: B. 10
-5C3 or 5 choose 3 refers to how many combinations are possible from 5 items, taken 3 at a time. To calculate combinations, we will use the formula nCr = n! / r! ... * (n - r)!, where n represents the total number of items, and r represents the number of items being chosen at a time.
-10 is the total number of all possible combinations for choosing 3 elements at a time from 5 distinct elements without considering the order of elements in statistics & probability surveys or experiments. The number of combinations for sample space 5 CHOOSE 3 can also be written as 5C3 in the format of nCr or nCk.
Step-by-step explanation: Hope this help :D