a)
6$m^{2}$ 58$dm^{2}$ = 6$m^{2}$ + $\frac{58}{100}$$m^{2}$ = $6\frac{58}{100}$$m^{2}$
19$m^{2}$ 7$dm^{2}$ = 19$m^{2}$ + $\frac{7}{100}$$m^{2}$ = $19\frac{7}{100}$$m^{2}$
43$dm^{2}$ = $\frac{43}{100}$$m^{2}$
b)
9$cm^{2}$ 58$mm^{2}$ = 9$cm^{2}$ + $\frac{58}{100}$$cm^{2}$ = $\frac{58}{100}$$cm^{2}$
15$cm^{2}$ 8$mm^{2}$ = 15$cm^{2}$ + $\frac{58}{100}$$cm^{2}$ = $\frac{58}{100}$$cm^{2}$
48$mm^{2}$ = $\frac{48}{100}$$cm^{2}$