Answer:
288J
Step-by-step explanation:
recall the formula for kinetic energy
KE = (1/2) mv²
where m is the mass (= 4kg) and v is the velocity(=12 m/s)
hence
KE = (1/2) (4)(12)² = 288J
Its A. x=4
procedure: 3*equation1 - 2*equation2 ⇒ x=4
You are solving for the height. Use the formula:
c² - b² = a² in which c = hypotenuse
(13)² - (5)² = a²
Simplify
169 - 25 = a²
144 = a²
Isolate the a. Root both sides
√144 = √a²
a = √144
a = √(12 x 12)
a = 12
C) 12 feet is your answer
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I think the last two are correct.
Hope it helps