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$a_n=a_1+(n-1)d \\ \\ a_2=a_1+d \\a_3=a_1+2d \\ a_5=a_1+4d \\ \\ \left \{ {{a_1*a_5=-32} \atop {a_2+a_4=4}} \right. \left \{ {{a_1(a_1+4d)=-32} \atop {a_1+d+a_1+3d=4}} \right. \left \{ {{a_1^2+4a_1d+32=0} \atop {2a_1+4d=4}} \right. \left \{ {{(a_1+2d)^2-4d^2+32=0} \atop {a_1+2d=2}} \right. \\ \\ \left \{ {{2^2-4d^2+32=0} \atop {a_1+2d=2}} \right. \left \{ {{4d^2=36} \atop {a_1+2d=2}} \right. \left \{ {{d=3 } \atop {a_1+2*3=2}} \right.$

a_1=-4" alt="\left \{ {{d=3 } \atop {a_1+2*3=2}} \right. \\ a_1+6=2 => a_1=-4" align="absmiddle" class="latex-formula">

$a_{11}=a_1+10d=-4+10*3=-4+30=26$