Determining size of whiteboard for projection

[Archie]

Good Afternoon,

A colleague and I are trying to determine the appropriate size for a 100" (diagonally) projection to appear in 1080p (which is a 1920x1080 or 16:9 ratio).

We used the good ol' Pythagorean to determine 9x^2 + 16x^2 = 100^2. This gave us that x is approximately 5.44.

Am I correct in assuming then that for the 100" projection that:

Height = 4.08 feet (5.44*9 / 12)
Width = 7.253 feed (5.44*16 / 12)

It's Friday... and we're too ready for the weekend for math. ^_^

 

[Ishuda]

Good Afternoon,

A colleague and I are trying to determine the appropriate size for a 100" (diagonally) projection to appear in 1080p (which is a 1920x1080 or 16:9 ratio).

We used the good ol' Pythagorean to determine 9x^2 + 16x^2 = 100^2. This gave us that x is approximately 5.44.

Am I correct in assuming then that for the 100" projection that:

Height = 4.08 feet (5.44*9 / 12)
Width = 7.253 feed (5.44*16 / 12)

It's Friday... and we're too ready for the weekend for math. ^_^

Yes, your method is correct. How so some ever, you really do need to use those grouping symbols
(9x)² + (16x)² = 100^{2
x = 5.44734710702843}