The answer would be 56.10
You need this key result: in any polygon, the sum of the interior angles is

where
is the number of sides of the polygon.
Your polygon has seven sides, and the measures of all angles are given. So, we can write

Again, we've simply written that the sum of all interior angles is the number of sides, minus two, times 180.
We can simplify both sides: we sum like terms on the left hand side, and we easily compute the right hand side:

and we can solve this equation for
by dividing both sides by 30:

Finally, the required angles is 
Answer:
Therefore a= 90°,b=54°, x=54°, y= 162°
Step-by-step explanation:
a=90°
a:b=5:3
5+3= 8
5/8 x A = 90
A is the sum of the angles of a and b divided in the ratio 5:3
5A/8 = 90
cross multiply
5A= 90 X8 = 720
5A=720
A= 720/5= 144°
b= 3/8 x 144 = 3x144/8 = 432/8 = 54
a= 90
b= 54
x:y is in the ratio of 1:3
the Sum of angles in a Quadrilateral is 360°
if the sum of a and b is 144°
then the reamining angles is 360-144= 216°
then x:y=1:3
1+3=4
x= 1/4 x 216= 54°
y= 3/4 x 216= 162°
Therefore a= 90°,b=54°, x=54°, y= 162°
we can see that b = x = 54°
Answer:
5280*13 = 16640
Step-by-step explanation:
5280*13 =
5280
* 13
-----------
52800
+ 15840
-------------
16640