A made$-$up truss structure is given below. It is pin supported at point A and supported by rollers at points

C and N$.$ For your convenience$/$solution the truss is shown again next page.

Determine the support reactions and the force in member OA$.$ You need to calculate the forces on

your own $($Answers: $Cy=49\mathrm{.}3KN$ Up$,Rn=23\mathrm{.}8KN$ Up perpendicular to the roller plane, $OA=$

$21\mathrm{.}5KN(C))$

The Answers are given but I want to see how they got the answers