Answer:
12x^2-4x
Step-by-step explanation:
5x + 4x^2 - 9x + 8x^2
Combine like terms
4x^2+8x^2+5x-9x
12x^2-4x
First you had to rewrite the problem with eighteen as the three times six is equal to eighteen.

Then you factor it out by the common term of six.

Final answer: 
Hope this helps!
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-Charlie
Yes, the triangles are similar because all of their angles are congruent. SImilar triangles have angles that are the same and sides that are proportional.
Answer: $12.32
Work: 22 x 0.44=9.68
22-9.68=12.32