this is the second question I don't undrstand
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Answer:
[tex]d=\sqrt{58}[/tex]
Step-by-step explanation:
Distance Formula: [tex]d=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}[/tex]
Simply plug in your coordinates into the distance formula to find the length of AB:
[tex]d=\sqrt{(9-2)^2+(4-1)^2}[/tex]
[tex]d=\sqrt{(7)^2+(3)^2}[/tex]
[tex]d=\sqrt{49+9}[/tex]
[tex]d=\sqrt{58}[/tex]