I think it is
1,000 <span>quintillion</span>
First, factor out a 3.
3(x² - 9)
In any quadratic ax² + bx + c, we can split the bx term up into two new terms which we want to equal the product of a and c.
In this case, we have x² + 0x - 9. (the 0x is a placeholder)
We want two numbers that add to 0 and multiply to get -9.
Obviously, these numbers are 3 and -3.
Now we have 3(x² + 3x - 3x - 9).
Let's factor.
3(x(x+3)-3(x+3))
<u>3(x-3)(x+3)</u>
There are multiple shortcuts which you could make here, FYI:
Instead of splitting the middle, if your a value is 1, you can go straight to that step (x+number)(x+other number).
Whenever you have a difference of squares, like a²-b², that factors to (a+b)(a-b).
X + y = 120000
0.15x - 0.10y = 5500
Multiply both sides of bottom by 100 to remove decimals
x + y = 120000
15x - 10y = 550000
Multiply both sides of top by 10
10x + 10y = 1200000
15x - 10y = 550000
Add the two
25x = 1750000
x = 70000
He paid $70,000 for the property that made a profit, and paid $50,000 for the property that lost value.
