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Work Shown:
Use the distance formula with the two points (x1,y1) = (-3,-8) and (x2,y2) = (10,-8)
[tex]d = \sqrt{(x_1 - x_2)^2 + (y_1 - y_2)^2}\\\\d = \sqrt{(-3-10)^2 + (-8-(-8))^2}\\\\d = \sqrt{(-3-10)^2 + (-8+8)^2}\\\\d = \sqrt{(-13)^2 + (0)^2}\\\\d = \sqrt{169 + 0}\\\\d = \sqrt{169}\\\\d = 13\\\\[/tex]
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As a shortcut, you can subtract the x values and apply the absolute value
d = |x1-x2| = |-3-10| = |-13| = 13
This shortcut only works because the y coordinates are the same.
