What is the x-value of the vertex?

f(x)=(x+2)2−1
x-value of the vertex:

What expression is equivalent to 42x-56y

If sin(x) = 0 and cos(x) = 1, what is tan(x)?

Select the correct answer from each drop-down menu. a system of equations and its solution are given below. system a complete the sentences to explain what steps were followed to obtain the system of equations below. system b to get system b, the equation in system a was replaced by the sum of that equation and times the equation. the solution to system b the same as the solution to system a.]