Question

Please help, thanks.

Answer 1

use the pythagoras theorem
12^2 = 3^2 + h^2
h = 3√15
h = 11.618950038622 (exact)
h = 11.62 (approximate)

Answer 2

`\text{Apply Pythagorean theorem,}\\ \\~~~~~~12^2 = 3^2 + h^2\\\\\implies h^2 = 12^2 -3^2\\\\\implies h^2 = 144-9\\\\\implies h^2 = 135\\\\\implies h = √(135)\\\\\implies h = 3√(15)\\\\\implies h \approx 11.62`