Answer:
y = 97°
Explanation:
Opposite angles in a quadrilateral inscribed in a circle sum ups to 180°
So following the rule:
A + C = 180°
y + 83° = 180°
y = 180° - 83°
y = 97°
We have,
Introduce variable 
such that 
The sum 
is therefore 
So,
(sadia's age)
(father's age)
Hope this helps :)
The area of plate which is covered by the napkin is equal to the area of folded napkin.
Before finding the area of folded napkin, we should find the dimension of the napkin.
Find the length of the leg side, the two leg has similar length.
perimeter = 38
l + l + 8 = 38
2l + 8 = 38
2l = 30
l = 15
Each leg is 15 cm long.
Find the area of folded napkin
area = 1/2 × s × s × sin of angle between the sides
area = 1/2 × 15 × 15 × sin 30°
area = 1/2 × 15 × 15 × 1/2
area = 225/4
area = 56.25
to the nearest whole number >> 56 cm²
The answer is third option
