Answer:
[tex]r = \frac{5}{2\sqrt{2} } \\r = -\frac{5}{2\sqrt{2}}[/tex]
Step-by-step explanation:
25= r•r•8 ⇔ 25/8 = r²
then
[tex]r^{2} =(\frac{5}{2\sqrt{2} } )^{2} \\\\Then\\\\r = \frac{5}{2\sqrt{2} } \\Or\\r = -\frac{5}{2\sqrt{2}}[/tex]
