PLEASE HELP ME!!! It’s High School Math. Algebra 2 and it’s on Big Ideas Math.
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Answer:
hope this will help you
[tex]let \: the \: angle \: be \: \alpha \\ \cos( \alpha ) = \frac{b}{h} \\ \cos(60) = \frac{x}{9} \\ \frac{1}{2} = \frac{x}{9} \\ x = \frac{9}{2} \\ x = 4.5[/tex]