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I really need help with this question!!

I really need help with this question!!-example-1

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The following are pairs of similar triangles:

  • OBN and OTS
  • ONG and OSE
  • OBG and OTE

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a. From
\Delta OBA\sim\Delta OTE we have


(OB)/(OT)=(OG)/(OE)\implies\frac{OB}4=(8.7)/(11.6)\implies OB=3

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b.
OT=OB+BT\implies4=3+BT\implies BT=1

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c. From
\Delta OBG\sim\Delta OTE we can find the length of BG:


(BG)/(TE)=(OB)/(OT)\implies(BG)/(12)=\frac34\implies BG=9

By the law of cosines, we can find the measure of angle BOG:


BG^2=OB^2+OG^2-2OB\cdot OG\cos\angle BOG


9^2=3^2+8.7^2-2\cdot3\cdot8.7\cos\angle BOG


\implies m\angle BOG\approx85.95^\circ

We use the law of sines to find the measure of angle OBG:


(\sin\angle BOG)/(BG)=(\sin\angle OBG)/(OG)\implies m\angle OBG\approx74.63^\circ

Finally,


\sin\angle OBG=\frac{OA}3\implies OA\approx2.89

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d.
OU=OA+AU\implies OU\approx2.89+0.9\approx3.79

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e.
OE=OG+GE\implies11.6=8.7+GE\implies GE=2.9

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f. See part c.
BG=9

User Kemal Turk
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