Phyllis (Full Time Private Tutor)'s answer to Meredy's Secondary 3 E Maths Singapore question.

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Phyllis (Full Time Private Tutor)
Phyllis (full Time Private Tutor)'s answer
3 answers (Tutor Details)
1st
(a)
Angle ACB = 31+20 = 51 deg
tan 51 = 12/BC
BC = 12/(tan 51)

(b)
tan 31 = 12/BD
tan 31 = 12/(BC + CD)
BC + CD = 12/(tan 31)
CD = [12/(tan 31) ] - BC

(c)
Area = 0.5 x 12 x CD

Please use your calculator to work out the rest of the answers!