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Trigonometry — Question 7

Original QCE Vault practice · 1 mark

Q7 · Practice questionTechnology-freeSimple familiar1 mark

QUESTION 7

In triangle

ABC

,

AB=10

,

AC=7

and

\angle A=60^\circ

. Determine

BC

.

Diagram for question 7

(A)

\sqrt{79}

(B)

\sqrt{51}

(C)

13

(D)

17

ABCD

Question linkSyllabus coverage

WORKED SOLUTION

Answer A

1 mark

ANSWER

A

Worked solution

By the cosine rule,

BC^2=10^2+7^2-2(10)(7)\cos60^\circ=79

.

Selects the correct option.

[1 mark]

Practice question aligned to the current QCAA syllabus; review the worked solution and marking criteria.

View the QCAA syllabus

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