Answer:
B. (3, 14).
Explanation:
Substitution means that you first solve for one variable, and then use that solution to find the other.
For example, if x = y, and x + 5 = 7, you can say that y + 5 = 7.
Now, moving on to the actual problem.
The first equation says that y = 6x - 4, and the second equation says y = 7x - 7.
That means for the first equation, instead of y, it is valid to say that 7x - 7 = 6x - 4.
7x - 7 = 6x - 4
7x - 6x = -4 + 7
x = 3.
You could put the x=3 into the y = 7x - 7 equation to find what the y-coordinate is.
y = 7 * 3 - 7
y = 21 - 7
y = 14.
And there you have your coordinates! (3, 14).
Hope this helps!