9514 1404 393
Answer:
10
Step-by-step explanation:
The distance formula is useful.
d = √((x2 -x1)^2 +(y2 -y1)^2)
d = √((7 -1)^2 +(12 -4)^2) = √(6^2 +8^2) = √(36 +64) = √100
d = 10
The distance between P and Q is 10.
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Additional comment
You may recognize the run : rise ratio of 6 : 8 = 3 : 4. This suggests a 3-4-5 right triangle with a scale factor of 2. If you're familiar with that Pythagorean triple, you can write down the answer as soon as you see the rise and run numbers.
