Answer:
15 miles
Step-by-step explanation:
Let's say the dock is at the origin on a coordinate plane and each unit is 1 mile. If the boat travels 9 mile due north, that means that we move up from the origin (0, 0) 9 units to point A (0, 9). Now, this boat moves 12 miles due west, so we will go 12 units to the left of (0, 9) to point B (-12, 9). See the attached drawing (sorry for the crudeness).
Notice that this is a right triangle with legs of 9 and 12. That means the distance from the boat to the dock is just the hypotenuse, so use the Pythagorean Theorem: distance = 
Thus, the answer is 15 miles.
Hope this helps!
Answer:
m = 124 degrees.
Step-by-step explanation:
The sum of the interior angles of a triangle is 180.
The angle opposite m + 56 + 68 = 180.
The angle opposite m = 56.
The angle opposite m + m = 180, so 56 + m = 180.
Angle m = 124.
Answer:
y = -5x - 23
Step-by-step explanation:
Write it in point - slope form:
y - 7 = -5(x + 6)
rearrange:
y - 7 = -5x - 30
y = -5x - 23
<span> -14x + 11y = 23
+2(7x - 3y = 37)
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0 + 5y = 97
y = 97/5
y = 19.4
7x - 3(19.4) = 37
7x - 58.2 = 37
7x = 37 + 58.2
7x = 95.2
x = 95.2/7
x = 13.6
Check
-14(13.6) + 11(19.4) = 23
-190.4 + 213.4 = 23
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