5% of 18,000 is 900 , hope this helps.
Answer:
80 lemons
Step-by-step explanation:
Let x represent the amount of lemons that were on the tree.
We can use this to set up an equation:

Note that percentages can also be written as that number over 100.

Simplify the fraction.

Multiply both sides by 5

Divide both sides by 2

There were 80 lemons on the tree before he picked the lemons.
Answer:
(2x - 9)(2x + 9)
Step-by-step explanation:
4x^2 - 81 = (2x - 9)(2x + 9)
-1 1, -2 2, 3 -3. Is this what you wanted? If no tell me in comments and maybe a can help fix.
2x+4=10
2x=6
x=3
2(3)+4= 10
(plus, on parallelograms like that, parallel sides are equal to each other)