00:01
In this problem, we're being asked to evaluate the given expression, x sub 1 plus x 2, all getting divided by 2, and we're told that x of 1 is equal to 4, and x sub 2 is equal to negative 7.
00:13
So when you're evaluating an expression, what we need to do first is substitute the values into our expression, meaning we need to substitute 4 in place of x of 1, and we're going to substitute negative 7 in place of x of 2.
00:27
So let's see what we have.
00:28
So we'll have 4, plus negative 7, and now it's all getting divided by 2.
00:36
Okay, well, now we can simplify by using the order of operations.
00:40
So the first we're going to do is simplify our numerator...