Answer:
x=16
Explanation:
If the triangles are similar then their sides are in proportion.
Set the proportions 20/(3x+8)=(x-1)/(x-1+27)
solve for x,
cross multiply
20(x+26)=(x-1)(3x+8),
distribute
20x+520= 3x² +8x-3x-8,
combine like terms
3x²-15x-528=0
solve using quadratic formula
x=16 and x= -11 reject because we cannot have negative measurements