1) Find the interior angle sum of a 36-gon.

6120°

720°

900°

1800º

Sum of interior angles = ( number of sides -2) x 180 degrees.

Sum = (36-2) x 180

Sum = 34 x 180

Sum = 6,120 degrees.

5=812a+9+3

step 1: simplify both sides of the equation.

5=812a+9+3

5=(812a)+(9+3)(combine like terms)

5=812a+12

5=812a+12

step 2: flip the equation.

812a+12=5

step 3: subtract 12 from both sides.

812a+12−12=5−12

812a=−7

step 4: divide both sides by 812.

812a /812 = -7/812

a= -1/116

so the answer is

a=   -1/116