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Formula to find Distance:
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![\text{Distance = } √(X2-X1)^2 + (Y2-Y1)^2)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/rmwq1mpjzomeko8or3zj1cfqh2qxxtsh3q.png)
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Find Distance between (5, 9) and (7, -7):
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X2 = 5, X1 = 7, Y2 = 9, Y1 = -7, therefore,
![\text{Distance = } √((9+7)^2 + (5-7)^2)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/svi3bxyiuj17eho23xyn61bd77f4p0phwl.png)
![\text{Distance = } √((16)^2 + (2)^2)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/ql7qjem7ehnhbnereyo4xtdmsuzd7ybrpf.png)
![\text{Distance = } √(256 + 4)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/lq9appe05xjruu16fhwtmb66oma88kbnor.png)
![\text{Distance = } √(260)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/9phc6fbme7ebgvowmfu93a9ey0tmf2atjn.png)
![\text{Distance = } 16.12 \text{ units}](https://img.qammunity.org/2019/formulas/mathematics/middle-school/w077230p2qdmi835i6mtbta0gxx894qnjf.png)
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Answer: 16.12 units========================================