hey user!
your answer is here..
given :-
height of the triangle = 26 + 13
= 39cm
base of the triangle = 45cm
area of the triangle = 1/2 × b × h
= 1/2 × 45 × 39
= 1755/2
= 877.5cm²
now,
radius of the circle is given = 13cm
area of the circle = πr²
= 22/7 × 13 × 13
= 3718/7cm²
therefore area of the shaded region = 877.5/1 - 3718/7
= 6142.5/7 - 3718/7
= 2424.5/7
= 346.35cm² ( approximately )
cheers!!