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).
Answer:
190 is 76% of 250
Step-by-step explanation:
We have, 76% × x = 190
Multiplying both sides by 100 and dividing both sides by 76,
we have x = 190 × 100/76
x = 250
If you are using a calculator, simply enter 190×100÷76, which will give you the answer.
Answer
Find out how many seconds faster has Alexandria's time then Adele's time .
To proof
Let us assume that seconds faster has Alexandria's time then Adele's time be x.
As given in the question
Adele Swam the length of the pool in 32.56 seconds. Alexandria swam the length of the pool in 29.4 seconds.
Than the equation becomes
x = 32.56 - 29.4
x = 3.16 seconds
Therefore the 3.16 seconds faster has Alexandria's time then Adele's time .
Hence proved
