OG详解-OG9 数学2 Q9

Choice A is correct. The solution to a system of equations is the ordered pair (x, y) that satisfies all equations in the system. It’s given by the first equation in the system that x+7 = 10. Substituting 10 for x+7 into the second equation yields 10² = y, or y = 100. The x-coordinate of the solution to the system of equations can be found by subtracting 7 from both sides of the equation x+7 = 10, which yields x = 3. Therefore, the ordered pair (3, 100) is a solution to the given system of equations.
Choice B is incorrect and may result from conceptual or calculation errors. Choice C is incorrect and may result from conceptual or calculation errors. Choice D is incorrect and may result from conceptual or calculation errors.