Respuesta :

4,9,16,a
a=25
clearly its squares of consecutive numbers

look at diagonal numbers, 4 and 8,9 and 18,16 and b. so, clearly, b=2*16=32

in fig 12, no of triangles= 2*(12*12)=288

p=(n+1)(n+1)
q=2*n*n

 try to see the pattern.