For this case we have that by definition, a function is of the form:

So, we have the following system of equations:

Equating the equations we have:

Adding 2x to both sides of the equation:

Subtracting 2 from both sides of the equation:

Dividing between -4 on both sides of the equation:

Thus, the value of the variable "x" is -0.5.
Answer:
-0.5
8 times 3 then 8 times 5 then add the two then write the rest of the expression
3*4*4=48
she can make 48 different sandwiches
The value of cos A is √(1 + x²)/ (1 - x²) /√1 + x
<h3>Trigonometric ratios</h3>
It is important to note that
sin A = opposite/ hypotenuse
cos A = adjacent/ hypotenuse
Then,
opposite = 
Hypotenuse = 
Let's find the adjacent side using the Pythagorean theroem



cos A = x/hypotenuse

cos A = √(1 + x²)/ (1 - x²) /√1 + x
Thus, the value of cos A is √(1 + x²)/ (1 - x²) /√1 + x
Learn more about trigonometric identities here:
brainly.com/question/7331447
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