Final answer:
To represent the situation where Brian scored x points and Joe scored 1/4 of the points, we can write the equation: x + 1/4x = 21 (option A). The value of x will give us the total number of points the team scored.
Step-by-step explanation:
To represent the situation where Brian scored x points and Joe scored 1/4 of the points, we can write the equation: x + 1/4x = 21 (option A). This equation represents the total number of points scored by both Brian and Joe. To find the total number of points the team scored, we can solve the equation by combining like terms and subtracting 1/4x from both sides. The resulting equation will give us the value of x, which represents the total number of points Brian scored. So, option A is the correct equation to represent the situation and the value of x will give us the total number of points the team scored.