Round to the nearest tenth

Answer:
7.0
Step-by-step explanation:
Tangents form right angles, so AOB is a right triangle.
Now using Pythagorean Theorem (A^2 + B^2 = C^2), plug in the values and solve inversely.
5^2 + B^2 = 8.6^2
25 + B^2 = 73.96
B^2 = 48.96
B = squareroot 48.96
B = 6.997 --> 7.0
Answer: r is 7
Step-by-step explanation:
ABO is a right triangle
[tex]a^{2} +b^{2} =c^{2} \\5^{2} +b^{2} =8.6^{2} \\25+b^{2} =73.96\\b^{2} =48.96\\b=6.997[/tex]