As shown in the figure, draw three semicircles with the three sides of the right triangle as the diameter. If the areas of the two small semicircles are known to be S1 = 8 and S2 = 18, then S3 =? A.10 B.13 C.26 D.25

As shown in the figure, draw three semicircles with the three sides of the right triangle as the diameter. If the areas of the two small semicircles are known to be S1 = 8 and S2 = 18, then S3 =? A.10 B.13 C.26 D.25

C
S1=(1/4)*PI*a^2
S2=(1/4)*PI*b^2
S3=(1/4)*PI*c^2=S1=(1/4)*PI*(a^2+b^2)=S1+S2=26