Answer:
y = 2x - 18
Explanation:
There are lots of different methods to do these types of questions, but this is the way i like to do it.
Coordinate (x1, y1) : (4, -10) and Gradient (m): 2
Start with this generic equation:
y- y1 = m(x-x1)
Substitute in the values they have given you:
y - (-10) = 2(x-4)
This becomes:
y + 10 = 2x - 8
Keep solving by moving the 10 over to the other side:
y = 2x -8-10
y = 2x - 18
An easy way to double check:
1) the coefficient of x is the slope. We got 2x, and the slope is 2, so that's correct.
2) Substitute x=4 into the equation, and we get -10, which is the exact coordinate that they gave us. This is also right.
Hope this helped : )