130 • .16 = 20.8 or 20 (4/5) or 104/5
Put the answer as 20.8 unless specified otherwise.
.16 is 16%
Answer: the original price was $60! <3
Step-by-step explanation:
Answer:
y = -6
Step-by-step explanation:
y is multiplied by 3 and 20 is added to the sum. We undo these operations in reverse order.
First we subtract 20 from both sides of the equation:
3y = -18
Then we divide both sides of the equation by 3 to undo the multiplication.
y = -18/3 = -6
The solution is y = -6.
Answer:
you're not doing anything wrong
Step-by-step explanation:
In order for cos⁻¹ to be a function, its range must be restricted to [0, π]. The cosine value that is its argument is cos(-4π/3) = -1/2. You have properly identified cos⁻¹(-1/2) to be 2π/3.
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Cos and cos⁻¹ are conceptually inverse functions. Hence, conceptually, cos⁻¹(cos(x)) = x, regardless of the value of x. The expected answer here may be -4π/3.
As we discussed above, that would be incorrect. Cos⁻¹ cannot produce output values in the range [-π, -2π] unless it is specifically defined to do so. That would be an unusual definition of cos⁻¹. Nothing in the problem statement suggests anything other than the usual definition of cos⁻¹ applies.
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This is a good one to discuss with your teacher.