As you can tell, the shape is split into two triangles.
Solve the first triangle (which is a isosceles, as their legs are the same measurement).
An isosceles triangle's measurement angles is: 1, 1, √2
1 = 4
1 = 4
√2 = 4√2
measurement of line AC = 4√2
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Use the Pythagoream theorem: a² + b² = c² (c being the hypotenuse)
a = 2
b = 4√2
c = c
Plug into corresponding terms:
(2)² + (4√2)² = c²
Simplify
4 + (4)(4)(√2)(√2)* = c²
*Note that two of the same roots multiplied together will result in a whole number
4 + 16(2) = c²
Simplify
16 x 2 = 32
32 + 4 = 36
c² = 36
Simplify. Isolate the c. Root both sides
√c² = √36
c = √36
c = 6
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(D) 6 is your answer
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hope this helps
