The given triangle is a Right angled triangle,
By applying trigonometry :
[tex] \boxed{\tan( \theta) = \frac{opposite \: \: side}{adjacent \: \: side} }[/tex]
- [tex] \tan(45 \degree) = \dfrac{7}{a} [/tex]
- [tex]1 = \dfrac{7}{a} [/tex]
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[tex]\mathrm{ ☠ \: TeeNForeveR \:☠ }[/tex]
