Find the missing length

Answer:
x = 45
Step-by-step explanation:
Corresponding sides of similar triangles will be in same ratio.
[tex]\dfrac{x}{x+18}=\dfrac{20}{28}[/tex]
Cross multiply
x*28 = 20*(x+18) {Use distributive method}
28x = 20x + 360
28x - 20x = 360
8x = 360
x = 360/8
x = 45