Answer:
Step-by-step explanation:
[tex](5m-m^3)+m(9m-25)\\\\m =3[/tex]
Substitute : m=3 into the given equation
[tex](5(3)-(3)^3)+3(9(3)-25)\\\\Follow\:the\:PEMDAS\:order\:of\:operations\\\\\mathrm{Calculate\:within\:parentheses}\:\left(5\left(3\right)-\\\left(3\right)^3\right)\::\quad -12\\\\=-12+3\left(9\left(3\right)-25\right)\\\\\mathrm{Calculate\:within\:parentheses}\:\left(9\left(3\right)-25\right)\::\quad 2\\=-12+3\times\:2\\\\\mathrm{Multiply\:and\:divide\:\left(left\:to\:right\right)}\:3\times\:2\::\quad 6\\=-12+6\\\\\mathrm{Add\:and\:subtract\:\left(left\:to\:right\right)}\:-12+6\:\\:\quad -6[/tex]