For the first triangle the sum of angles in any given triangle is equal to 180 degrees.
The equation for the first triangle would be: 60+80+x+51= 180
Solving it we get: 191+x=180
x=-11.
The second triangle’s equation is: 90+45+52+x= 180
Solving it we get: 187+x=180
x=-7
The third triangle’s equation is: 4+7x= 90
This is because it is a right angle.
Solving it we get: 12.2 (rounding) 
x=about 12.2
For the fourth triangle the equation is: 6x-5+5x=105 (we subtract 75 to 180 to get the sum of the other two angles)
Solving it we get: 11x=110
x=10.
Hope this helps! ( and if you can please give brainliest, it would mean a lot!)
        
                    
             
        
        
        
Easy
y=2x-7
sub 2x-7 for every y you se inother equation
x+2(2x-7)=1
x+4x-14=1
5x-14=1
add 14 both sides
5x=15
divide 5
x=3
sub back
y=2x-7
y=2(3)-7
y=6-7
y=-1
(3,-1) is solution
        
             
        
        
        
56,232 there you go you should try this one i did it like this
 -68,280
  12,048
 
56232
        
             
        
        
        
Answer:
125i. 
Step-by-step explanation:
5^3 is 125 i^2 is -1 so i^8 is positive and you have 1 i left. 
 
        
             
        
        
        
Answer:
B) (-2,3)
Step-by-step explanation:
Graph all your points. No count the distance from point A to B. divide in half .