Find the length of the third side. If necessary, round to the nearest tenth. 4 5
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Solution :
Let,
We know that,
[tex]{ \longrightarrow \bf \qquad \: (AB) {}^{2} +( BC) {}^{2} = (AC) {}^{2} }[/tex]
[tex]{ \longrightarrow \sf \qquad \: (AB) {}^{2} +( 4) {}^{2} = (5) {}^{2} }[/tex]
[tex]{ \longrightarrow \sf \qquad \: (AB) {}^{2} = (5) {}^{2} - ( 4) {}^{2} }[/tex]
[tex]{ \longrightarrow \sf \qquad \: AB = \sqrt{(5) {}^{2} - ( 4) {}^{2}} }[/tex]
[tex]{ \longrightarrow \sf \qquad \: AB = \sqrt{25 - 16 }}[/tex]
[tex]{ \longrightarrow \sf \qquad \: AB = \sqrt{9 }}[/tex]
[tex]{ \longrightarrow {\pmb {\bf\qquad \: AB = 3}}}[/tex]
Therefore,