Answer: $12.57 hope this helps
5) So for parallelogram ABCD, ∠B ≅ ∠D, and ∠A ≅ ∠C. Further, ∠B and ∠A are supplementary (i.e., their sum is 180°), and ∠D and ∠C are also supplementary.
So, we have that m∠B = m∠D. Therefore,
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Now, let's substitute for x back into the expression for either ∠B or ∠D to find it's angle measure.
m∠B =
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Now, remember that ∠B or ∠D are supplements of ∠A.
So, m∠B + m∠A = 180°.
That means m∠A = 180° – 72° = 108°.
That seems reasonable, because A appears to be an obtuse angle.
To obtain the square root of 16x^36, the coefficient portion (16) will not present any problems since 16 is a perfect square. However, for a variable with an exponent, the exponent is to be multiplied by 1/2 since the square root symbol is equal to raising the term inside to the power of 1/2. This is shown below:
sqrt (16 x^36) = 4 * x^36(1/2) = 4 * x^18
Therefore, the correct answer is 4x^18.