9.3 Arcs and Angles 1b

What happens when you inscribe and angle in a semicircle?

Click and drag point D. What do you notice about angle D? What do you notice about the relationship between angle B and angle C?

[b]Angles Inscribed in a Semicircle Conjecture:[/b] Angles inscribed in a semicircle are _____________.

right angles obtuse angles straight angles

[img width=172,height=172]https://lh5.googleusercontent.com/GHbCJ6CQLdzF4VngXGJAZbOoSwN0eF2tB0Ba90eoMn4AAOiHXELQMltbKPapn2VgkNOzsfmzOmoHMS50w0gNhMm1F-fFzMOUCXNOT8g-iUSYg7X2cEXOBgwsTWQHUSBGKCzt8hlt[/img]

[math]d=59^\circ[/math] and [math]e=90^\circ[/math] [math]d=180^\circ[/math] and [math]e=45^\circ[/math] [math]d=90^\circ[/math] and [math]e=39^\circ[/math]

9.3 Arcs and Angles 1b

What happens when you inscribe and angle in a semicircle?

Information: 9.3 Arcs and Angles 1b