The point that is not on the straight line y= 2x-1 the answer is (-2,7) but i don’t understand why that is the answer, dumb it down

-2 is the x coordinate and 7 is the y coordinate. If you plug them into the equation y= 2x - 1, you end up with 7 = 2(-2) - 1; 7 = -4 -1; 7 = -5 which isn’t true so you know that point isn’t on the line.

For example, let’s say you have an x coordinate for a point on the line but need to figure out what the y coordinate is. Let’s say x = 3. You plug 3 in for x in the equation y = 2x -1 and solve for y.

So y = 2(3) -1 which is y = 6-1 which is y = 5 So the answer would be (3,5) (x-coordinate, y-coordinate). You can check your answer by plugging 5 into the equation for y and solving for x.

If you take (3,5) and plug them into the equation, y = 2x - 1, 5 = 2(3) - 1 which is 5 = 6 - 1 which is 5 = 5. You know the coordinates (3,5) belong to a point on the line because the equation matches.

I went the long way around on the explanation and I hope I didn’t confuse you!