yeah the picture sums it up, I just dont remember how to do this

Answer and Step-by-step explanation:
To find the length of AB, we have to use Distance Formula.
Distance Formula takes two points on a graph, and puts it into the following formula to calculate the distance between those two points.
The formula:
D = [tex]\sqrt{(x_{2} - x_1)^2 + (y_2 - y_1)^2 }[/tex]
Where:
D = The Distance between two points
[tex]x_2[/tex] = The x value of the second point
[tex]x_{1}[/tex] = The x value of the first point
[tex]y_2[/tex] = The x value of the second point
[tex]y_{1}[/tex] = The x value of the first point
Point A will be the first point and point B will be the second point. All we have to do now is plug those points into the formula and solve.
[tex]\sqrt{(10 - 5)^2 + (0 - 10)^2 }\\\\\\\\\sqrt{(5)^2 + (- 10)^2 }\\\\\\\\\sqrt{25 + 100 }\\\\\\\\\sqrt{125}\\\\\\\\\sqrt{125} = 5\sqrt{5}[/tex]
The length of side AB is [tex]5\sqrt{5}[/tex] units, or 11.18 units.
I hope this helps!
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