Answer:
See solution
Explanation:
Similar triangles have proportional corresponding sides.
1.
![(x)/(5)=(3)/(3+3)\Rightarrow 6x=15,\ x=(5)/(2)=2.5.](https://img.qammunity.org/2020/formulas/mathematics/high-school/vf3963q4um2e0r3gsfbrqkbmnfae8w21g0.png)
2.
![(x)/(18)=(15)/(15+7.5)\Rightarrow 22.5x=15\cdot 18,\ x=(270)/(22.5)=12.](https://img.qammunity.org/2020/formulas/mathematics/high-school/vu4zamq5y2kfxo48dydoz09d3odnwv9iu4.png)
3.
![(x)/(5)=(8+4)/(4)\Rightarrow 4x=60,\ x=(60)/(4)=15.](https://img.qammunity.org/2020/formulas/mathematics/high-school/48c72hu5w61thn3m1o78eunkee5g8zpaj5.png)
4. Angles ACB and ECD are congruent as vertical angles. Angles BAC and DEC are congruent (given), then ΔABC and ΔEDC are similar by AA theorem.
5. MN=NP=8 (given), NR=NQ=8+10=18 (given), angle N is common, then ΔNMP and ΔNQR are similar by SAS theorem.