The answer is 4*\sqrt(2), or 5.7 if rounded to the nearest tenth digit. Notice that this is a right triangle (F is the right angle). The length of FG and FE are both 4 units on the diagram. Therefore, according to the Pythagorean theorem, the length of EG is \sqrt(4^2+4^2)=4*\sqrt(2), which is about 5.7.
Answer:
12 units
Step-by-step explanation:
B - A = (7, 8) - (-5, 8) = (7 -(-5), 8 -8) = (12, 0)
The distance is then ...
d = √(12² + 0²) = √12²
d = 12
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Of course, when you graph these points (actually or mentally), you can see that they are 12 units apart on the line y=8. You don't need to do any fancy calculation to discover the difference between -5 and 7.