The triangles are similar.
What is the value of x?
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Answer:
Step-by-step explanation:
using proportion
12 : 3 = x : 4
x = 12 * 4 : 3
x = 48 : 3
x = 16
using Pythagorean theorem
√(20²-12²) =
√(400 - 144) =
√256 =
16