Answer:
Hello!!! Princess Sakura here ^^
Explanation:
For question number 8 all you have to do is add all the sides and make them equal to 180 so when you make it into an equation it'll look like this...
![10x-11+3x+1+3x-2=180](https://img.qammunity.org/2021/formulas/mathematics/high-school/gld9imcckblze14y0km04szya6jqwhy1sr.png)
Now you combine like terms then solve...
![10x-11+3x+1+3x-2=180\\16x-12=180\\16x=192\\x=12](https://img.qammunity.org/2021/formulas/mathematics/high-school/r8mjs2hxgt6usnuhir2hm4n9382xx77zmp.png)
So now you got x = 12.
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For question number 10 you should now that those two angles inside add up to the angle on the outside so if you know that those two angles add up to the outer angle, you should make an equation like this...
![11x-1+20x-3=151](https://img.qammunity.org/2021/formulas/mathematics/high-school/wcjysxrm4g30g8a7gibzay6mapy7aimt8u.png)
Now combine like terms and solve...
![11x-1+20x-3=151\\31x-4=151\\31x=155\\x=5](https://img.qammunity.org/2021/formulas/mathematics/high-school/x5wzfx5akx102v0cv9l4vhfqrhsnrk2pn8.png)
So now you have x = 5.