Question

Hi, can you help me to solve this exercise, please!

Answer 1

Given:

IJK is the right triangle.

`\angle J=90^(\circ),\angle I=60^(\circ),IK=2\sqrt[]{21}`

Use the cosine ratio,

`\begin{gathered} \cos I=\frac{adjacent\text{ side}}{\text{hypotenuse}} \\ \cos 60^(\circ)=(IJ)/(IK) \\ \cos 60^(\circ)=\frac{IJ}{2\sqrt[]{21}} \\ (1)/(2)=\frac{IJ}{2\sqrt[]{21}} \\ IJ=\frac{2\sqrt[]{21}}{2} \\ IJ=\sqrt[]{21} \end{gathered}`

Answer:

`IJ=\sqrt[]{21}`