All triangles interior angles equal 180
So these 3 angles = 180
Answer:
1)
2) 
3)
4)
Step-by-step explanation:
The slope formula of the line that pass across two points P1(x1,y1) and P2(x2,y2) is:

You can use this formula to solve all the four points:
1)

2)

3)

4)

4x+5y=7
y=3x+9
1) 4x+5(3x+9)=7 2) y=3(-2)+9
y= -6 +9
4x+15x+45=7 y=3
19x+45=7
19x= -38
x= -2
x is -2 and y is 3
Answer:
what!!!!!!!!!!!!!!!!!! so only for dudesssssssss