Answer:
<em>A) (-5,7)</em>
Step-by-step explanation:
<u>Functions and Relations</u>
A set of values A can have a relation with another set B as long as at least one element of A has at least one image in B. Functions are special relations where each element of A (the domain of the function) has one and only one image on B (the range of the function).
By looking at the options, we can see that x=9, x=-8, and x=-1 already have defined values in Y, so if we define another value for any of them the relation will stop being a function. The only possible choice to preserve the function is the option

To find this, turn the word question into an equation.
"One less than" means - 1, which is 1 being subtracted from something.
"half a number" means 1/2x, since 1/2 is half and x is unknown.
"is 12" means = 12, which is something equals 12.
Putting this in order would be 1/2x, then - 1, then = 12.
As an equation, this is 1/2x - 1 = 12.
So the equation is 1/2x - 1 = 12
Now you must find the number by solving this equation.
1/2x - 1 = 12
First, add 1 to both sides.
12 + 1 = 13
1/2x = 13
Now multiply both sides by 2.
This way, x will be isolated since 1/2x • 2 = 1x, and 1x = x.
13 • 2 = 26
x = 26
The number is 26.
Answer:

Step-by-step explanation:
Factorise the numerator and denominator
8a² - 2 ← factor out 2 from each term
= 2(4a² - 1) ← 4a² - 1 is a difference of squares
= 2(2a - 1)(2a + 1)
4a² + 4a + 1 ← is a perfect square
= (2a + 1)²
Thus

=
← cancel (2a + 1) on numerator/ denominator
= 
= 