$9\mathrm{.}4$ An llcorner$84\frac{1}{2}$ has staggered holes for $\frac{7}{8}-$in$.$ diameter bolts, as shown in Figure P$9\mathrm{.}4.$ Determine the net area $,$ centroid $\stackrel{}{x}=0\mathrm{.}854in.).$

Equation $9\mathrm{.}5$

$U=1-\frac{(\stackrel{}{x})}{L}$

Given:

A$913$ Steel $Fy=70$ksi,$Fu=90$ksi

FIGURE P$9\mathrm{.}4$ Staggered long leg angle connection.