Answer:
y = x
Explanation:
Slope-intercept form is the form that looks like
... y = mx + b . . . . . . for slope m and y-intercept b
The line connecting points D and E has slope 1 and y-intercept 0, so the equation is ...
... y = 1·x + 0
... y = x . . . . . . without the identity elements
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Comment on the marked choice
The choice that is marked is the equation in point-slope form using the point E (4, 4). That is not the form requested by the problem.