Question

Question #e7d7d

Answer 1

See explanation

Explanation:

Compare to the standardised equation of a strait line `y=mx+c`

Where `m` is the gradient (slope) and `c` is the y-intercept.

Given:

`y=x+1`
`y=x-1`

Although not written the variable `m` is there. It is of value 1.

So both lines have the same gradient (slope -> m=1)

As each 'crosses' the y-axis (y-intercept) in different places and they are parallel to each other they never cross, So there is not a common value

THUS IT IS `ul("WRONG")` TO STATE THAT: `" "x+1=y=x-1`
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I am only doing this for one of the equation. You can do the other one by following the same method.

For `y=x+1`

Determine the x-intercept (crosses the x-axis at `y=0`)

Set `y=0=x+1`

Subtract 1 from both sides `=> x=-1`

Determine the y-intercept (crosses the y-axis at `x=0`)

Set `x=0 ->y=0+1 => y=1`
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