The dimensions of ab in the equation P = a−t2bx2 where P is pressure, x is distance and t is time, are:

P=a−t2bx2=abx2−t2bx2As per principle of dimensional homogeneity each term in the equation must carry the dimension of pressure.P=abx2⇒ab=Px2=ML−1T−2L2⇒ab=MLT−2