Answer:
x = 7
Step-by-step explanation:
The whole triangle and the small triangle are similar. Therefore the sides are in proportion.
We have the equation:
[tex]\dfrac{(2x+10)+3}{40+5}=\dfrac{3}{5}\\\\\dfrac{2x+13}{45}=\dfrac{3}{5}\qquad\text{cross multiply}\\\\5(2x+13)=(45)(3)\qquad\text{divide both sides by 5}\\\\2x+13=(9)(3)\\\\2x+13=27\qquad\text{subtract 13 from both sides}\\\\2x=14\qquad\text{divide both sides by 2}\\\\\boxed{x=7}[/tex]
