Todeterminethesurfaceareaofsolid$CXYZ,$wedeterminetheareaofeachofthefourtriangularfacesandsumthem.Areasof$△CZX$and$△CZY:$Eachofthesetrianglesisright−angledandhaslegsoflengths6and8;therefore,theareaofeachis$12(6)(8)=24$.Areaof$△CXY:$Thistriangleisequilateralwithsidelength$6.$Wedrawthealtitudefrom$C$to$M$on$XY.$Since$△CXY$isequilateral,then$M$isthemidpointof$XY.$Thus,$△CMX$and$△CMY$are$30∘$−$60∘$−$90∘$triangles.Usingtheratiosfromthisspecialtriangle,$$CM=√32(CX)=√32(6)=3√3.$$Since$XY=6,$theareaof$△CXY$is$$12(6)(3√3)=9√3.$$Areaof$△XYZ:$Wehave$XY=6$and$XZ=YZ=10$anddropanaltitudefrom$Z$to$XY.$Since$△XYZ$isisosceles,thisaltitudemeets$XY$atitsmidpoint,$M,$andwehave$$XM=MY=12(XY)=3.$$BythePythagoreanTheorem,ZM=√ZX2−XM2=√102−32=√91.Since$XY=6,$theareaof$△XYZ$is$$12(6)(√91)=3√91.$$Finally,thetotalsurfaceareaofsolid$CXYZ$is$$24+24+9√3+3√91=48+9√3+3√91.$$
.