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Pls help with all the questions

Pls help with all the questions-example-1
User Youssman
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1 Answer

13 votes
13 votes

Answer:

Explanation:

Since, CD is an altitude, ∠CDB will be a right angle.

m∠CDB = m∠CDA = 90°

By applying triangle sum theorem in ΔABC,

m∠CAB + m∠CBA + m∠ACB = 180°

20° + m∠CBA + 90° = 180°

m∠CBA = 180° - 110°

= 70°

Therefore, m∠CBD = 70°

By applying triangle sum theorem in ΔBCD,

m∠BCD + m∠CDB + m∠DBC = 180°

m∠BCD + 90° + 70° = 180°

m∠BCD + 160° = 180°

m∠BCD = 20°

m∠CAD = m∠A = 20°

m∠ACD = 90° - m∠BCD

= 90° - 20°

m∠ACD = 70°

User Geethu Vinod
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2.4k points