Answer:
(3, 1) is a solution
Explanation:
If the coordinates are solutions of the equation, you should be able to solve the equation to get the y-value when you input the x-value;
So in the case of (3, 1), input x = 3 and solve for y:
(3) + 4y = 7
4y = 4
y = 1
Solving the equation gives y = 1, which is the same as the given coordinates, hence it is a solution or, in other words, this point falls on the line graphed by the equation