Answer:
f(-2) = +2
Step-by-step explanation:
Let x = -2
So,
f(x) = 4x + 10
Substituting the value of x gives ,
f(-2) = 4 × (-2) + 10 = 10 - 8 = 2
Example 1. Let us start with the functionf(x) = x2. We have

So

which means f '(a) = 2a.
What about the derivative of f(x) = xn. Similar calculations, using the binomial expansion for (x+y)n (Pascal's Triangle), yield

Let me help you with this :)
John = x
Mike = y
x = 4 + 3y (4 more than 3 times)
x + y = 20 (we put the x above into this equation)
4 + 3y + y = 20
4y = 16 (we transfers the 4 on the left side to the right side and subtract it from the 20)
y = 4 (the answer is 4)
we use this for the equation:
x = 4 +3*4
x = 16
John is 16 years old and Mike is 4 years old :)
-2x = -1
x = 1/2
Any equation that returns x=1/2 is a solution to this problem. For example, x= (3•4)/6 can be simplified so that x=1/2
