Answer: -4
Step-by-step explanation: The equation is a simple function having two variables x and y. f(x) can also be written as y.
Therefore, another way to write a function is y = 10-2x.
The question requires you to insert the value of one variable and calculate the other. In this case you have to find the value of function when x=7.
Insert 7 in place of x. So, the equation will look as follows.
f(x) = 10 - 2*7
f(x) = 10 - 14
f(x) = -4
Therefore, when x=7 the value of our function f(x) is equal to -4.