(Refer to the attached image)
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[tex]\sf Sine \ Rue : \ \dfrac{\sin A}{a}=\dfrac{\sin B}{b}=\dfrac{\sin C}{c}[/tex]
Given following:
Solve for b (distance between school and mall):
[tex]\dashrightarrow \sf \dfrac{\sin 56}{38} = \dfrac{\sin 77}{b}[/tex]
[tex]\dashrightarrow \sf b= \dfrac{38\sin 77}{\sin 56}[/tex]
[tex]\dashrightarrow \sf b= 44.6615 \quad \approx \quad 45[/tex]