Question

Is it true that a line with slope 1 always passes through the origin? Explain your reasoning.

Answer 1

A line with slope=1 always slopes up at an angle of 45 degrees, but you can move the line up or down, to cross the y-axis anywhere. /// The same wheelchair ramp can be built in any office of a 90-story office building.

Answer 2

It is not true because the y-intercept determines where you begin when plotting the points. If your line is something like y=x+3 or any intercept besides 0, the line will not always cross through the origin. 
That's what the line y=x+3 would look like: