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User Utxeee
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1 Answer

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Answer:

m∠DAC = 72°

Explanation:

Figure ABCD is a parallelogram.

As the diagonals BD and AC intersect each other, they form two pairs of vertical angles. Since the vertical angles created by two lines intersecting each other are congruent:

⇒ m∠AFD = m∠BFC = 49°

The interior angles of a triangle sum to 180°. Therefore, for ΔADF:

⇒ m∠DAF + m∠AFD + m∠FDA = 180°

From inspection of the given parallelogram, m∠FDA= 59°.

Therefore, substitute the measures of ∠AFD and ∠FDA into the equation and solve for ∠DAF:

⇒ m∠DAF + 49° + 59° = 180°

⇒ m∠DAF + 108° = 180°

⇒ m∠DAF = 72°

As m∠DAF = m∠ DAC, then m∠DAC = 72°.

User Kamprath
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