this is a trigonometry question .
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Answer:
AB ≈ 5.6 cm
Step-by-step explanation:
Using the cosine ratio in the right triangle
cos62° = [tex]\frac{adjacent}{hypotenuse}[/tex] = [tex]\frac{AB}{BC}[/tex] = [tex]\frac{AB}{12}[/tex] ( multiply both sides by 12 )
12 × cos62° = AB , thus
AB ≈ 5.6 cm ( to 1 dec. place )