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Find the values of x and y

Find the values of x and y-example-1

1 Answer

3 votes

You can use a tangent:


tangent=(opposite)/(adjacent)

We have opposite = 17 and adjacent = x.


\tan30^o=(\sqrt3)/(3)

substitute:


(17)/(x)=(\sqrt3)/(3) cross multiply


x\sqrt3=(3)(17) multiply both sides by √3


x(\sqrt3)(\sqrt3)=51\sqrt3


3x=51\sqrt3 divide both sides by 3


x=17\sqrt3

Use the Pythagorean theorem:


y^2=(17\sqrt3)^2+17^2\\\\y^2=289(\sqrt3)^2+289\\\\y^2=289\cdot3+289\\\\y^2=867+289\\\\y^2=1156\to y=√(1156)\\\\y=34

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Other method.


30^o-60^o-90^o triangle.

The sides are in the ratio
1:2:\sqrt3\to17:y:x

Therefore


17:(2\cdot17):(17\sqrt3)\to17:34:17\sqrt3\to x=34,\ y=17\sqrt3


User Simon Byrne
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