Answer:

Step-by-step explanation:
y = 18 + 3x²
- 18 - 18
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I am joyous to assist you anytime.
Let us cross multiply.
5/9=10/x
9 x 10= 5x
90=5x
90 <u />÷ 5= 5x <span>÷ 5
18=x
So, the answer is 18. I hope this helped you, since I just learned cross multiplication last week.</span>
U technecally wrote the answer