Which kind of triangle exists if the side measures are 3, 9, and 10? i thought the answer was acute but my teacher marked it wrong and told me the correct answer was obtuse could someone explain why it would be obtuse?

Step-by-step explanation:

    There is a rule that if c^2 > a^2 + b^2, then it is an obtuse triangle.

    *c is the longest side

     I attached more information on it below.

arithmetic sequence: a sequnce in which the diffrence between any two consecutive terms is the same

step-by-step explanation:

δabc ≅ δdcb by sas because

db ≅ ac . . given (side)

bc ≅ bc . . reflexive property (side)

∠dbc ≅ ∠ acb . . alternate interior angles where transversal bc crosses parallel lines bd and ac (included angle)