please help quick!! i have no idea what to do :(

Answer:
1.8
Step-by-step explanation:
Since 5 and 1 are corresponding, the scale factor of the smaller triangle is 1/5. since we need to know x and the corresponding side to x is 9, 9 divided by 5 is 1.8. Hope this helps <3
Your answer will definitely 1.8
x=1.8
Hoped I helped!
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