Completing the square follows the principle of taking

and converting it into

where d is the 'correctional number' as I like to call it - i.e. the number that converts the expanded bracket into the +c, since the expanded bracket will give us

.
In this case, 2/2=1 so we have the first part:

.
Expanding this gives us

. We need c to be 9, so we can just add 8.
Putting this together:

Now we can solve it more easily.
Rearranging:
Answer:
raoul is 16 and estaban is 22
Answer:
From top to bottom:

Step-by-step explanation:
We are given the piecewise function:

Row 1:
We want to find g(-2).
Since -2 is less than (or equal to) 2, we will use the first equation. Thus:

Row 2:
Likewise, 0 is less than or equal to 2. We will continue to use the first equation:

Row 3:
2 is not less than 2 but it is equal to 2. So we will continue to use the first equation:

Row 4 and 5:
Both 4 and 6 are greater than 2. Thus, we will use the second equation. Therefore:

Answer:
Below
Step-by-step explanation:
● x^2 + 11x + 121/4 = 125/4
Substract 125/4 from both sides:
● x^2 + 11x + 121/4-125/4= 125/4 -125/4
● x^2 + 11x - (-4/4) = 0
● x^2 +11x -(-1) = 0
● x^2 + 11 x + 1 = 0
This is a quadratic equation so we will use the determinanant (b^2-4ac)
● a = 1
● b = 11
● c = 1
● b^2-4ac = 11^2-4*1*1 = 117
So this equation has two solutions:
● x = (-b -/+ √(b^2-4ac) ) / 2a
● x = (-11 -/+ √(117) ) / 2
● x = (-11 -/+ 3√(13))/ 2
● x = -0.91 or x = -10.9
Round to the nearest unit
● x = -1 or x = -11
The solutions are { -1,-11}
There are 9 numbers less than 10. 1,2,3,4,5,6,7,8,9
And there are 2 multiples of 15. 15,30
There are 11 of the 40 cards that are either less than 10 or multiples of 15, so the answer is B