So if 123 x 47= 5781, 123 x 0.47= 57.81, why? because its exactly like dividing the number by 100, instead of dividing in the end, we divided one of the multipliers :)
The answer is 6(x^2 -1) I have provided a picture with my work and the answer
4b - 6b + 19
Answer : -2b + 19
let the other leg be x cm.
(5)^2+(x)^2=(12)
25+(x)^2=144
(x)^2=144-25
x=√119
x=10.9