Similar Triangles

  1. $70^{\circ}$
  2. $65^{\circ}$
  3. $45^{\circ}$
  4. $45^{\circ}$


  5.  

    $\eqalign{\dfrac{25}{30}&=\dfrac{x}{20}\\30x&=500\\x&=\dfrac{500}{30}=16\dfrac{2}{3}}$


  6.  

    $\eqalign{\dfrac{20}{30}&=\dfrac{x}{27}\\30x&=540\\x&=\dfrac{540}{30}=18}$

  7. $40^{\circ}$
  8. $90^{\circ}$
  9. $50^{\circ}$


  10.  

    $\eqalign{\dfrac{6}{8}&=\dfrac{x}{12}\\8x&=72\\x&=9}$


  11.  

    $\eqalign{\dfrac{6}{8}&=\dfrac{x}{10}\\8x&=60\\x&=7\dfrac{1}{2}}$

  12. $60^{\circ}$
  13. $50^{\circ}$
  14. $70^{\circ}$


  15.  

    $\eqalign{\dfrac{36}{42}&=\dfrac{x}{30}\\42x&=1080\\x&=\dfrac{180}{7}}$ So, CE=$\dfrac{180}{7}$ $\eqalign{\dfrac{36}{42}&=\dfrac{x}{27}\\42x&=972\\x&=\dfrac{162}{7}}$ So, DC=$\dfrac{162}{7}$ Perimeter= $36+\dfrac{162}{7} + \dfrac{180}{7}=84.86$