Mathematical Methods — Question 7

QCAA 2024, Paper 2 · 1 mark

Q7 · 2024 · Technology-activeSimple familiar1 mark

QUESTION 7

Identify the possible values for

a

in the triangle.

(A)

13.5^\circ

126.5^\circ

(B)

53.5^\circ

126.5^\circ

(C)

53.5^\circ

86.5^\circ

(D)

13.5^\circ

86.5^\circ

ABCD

WORKED SOLUTION

1 mark

ANSWER

B —

53.5^\circ

126.5^\circ

Worked solution

Using the sine rule,

\sin a/10=\sin40^\circ/8

, so

\sin a=(10/8)\sin40^\circ

. This gives

a\approx53.5^\circ

180^\circ-53.5^\circ=126.5^\circ

, so option B.

Selects option B.

[1 mark]

Worked explanation by QCE Vault; correct option verified against the QCAA answer key.