Those usually mean the variable for the side length for a triangle.
The sum of angle AOB and angle BOC is equal tot he angle of AOC so
6x+5 +4x-2 = 8x+21
10x+3=8x+21
Subtract three and 8x from both sides
2x=18
Divide by two
x=9
Hope this helped!
4. 70
5. 80
6. 151
7. 73
8. 741
9. 7,739
or you can use the calculator next time
3:1 should be the answer.
Get one x+y=3 to y=x+3 and plug it into x-y=1 and you get x-(x+3)=1. Destitute the x and solve. Once you get what x equals plug it to to either equation for the value of x and solve for y
