Answer:x=1
Step-by-step explanation:
 
        
             
        
        
        
For these fractions, you need to find a number that can divide the numerator and denominator by the same number. It needs to be simplified down till it can't be simplified any more.
1. 1/9
2. 12/18
3. 5/6
4. 36/45
5. 5/8
6. 6/8
7. 10/12
8. 20/36
 
        
                    
             
        
        
        
We know that
The exterior angle measures of a polygon must add up to 360°, 
therefore
 360°/72°=5 exterior angles
so
5 exterior angles, would mean 5 interior angles and therefore  5 sides to the polygon
The exterior angle and the interior angle of any polygon are supplementary and must add up to 180°.
exterior angle+interior angle=180°
interior angle=180°-exterior angle
interior angle=180°−72°-------> 108°
Each interior angle is 108°
The sum of the interior angles would be 
5*108°=540°
the answer is
540°
 
        
        
        
Answer:
60
Step-by-step explanation:
420 divided by 7
 
        
             
        
        
        
Answer:
(1,4)
x= 1
y= 4
(I checked on desmos and this is correct)
Step-by-step explanation:
 I'm going to solve this by substitution 
To do this we need to get a variable by istelf in any equation
We'll start with 18x-2y=10
We can add 2y and divide by 2 to get
y=9x-5
This is what y will equal for now and we can plug this in for y in the second equation
3x+16(9x-5)=67
This is rather easy to solve 
147x-80=67
147x=147
this means that x=1
We can then use this value for x and plug it into any equation
let's just do the first one
18*1-2y=10
This is easy to solve as well and you should get
-2y=-8
y=4
this means that x=1
y=4