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2 years ago

In the diagram below, AC and CB, AB and CD, and m(angle)A=33 degrees. Find M(angle)B

Mathematics

1 answer:

hoa [83]2 years ago

7 0

Answer:

15°.

Step-by-step explanation:

1. Angles ADC and CDB are supplementary, thus

m∠ADC+m∠CDB=180°.

Since m∠ADC=115°, you have that m∠CDB=180°-115°=65°.

2. Triangle BCD is isosceles triangle, because it has two congruent sides CB and CD. The base of this triangle is segment BD. Angles that are adjacent to the base of isosceles triangle are congruent, then

m∠CDB=m∠CBD=65°.

The sum of the measures of interior angles of triangle is 180°, therefore,

m∠CDB+m∠CBD+m∠BCD=180° and

m∠BCD=180°-65°-65°=50°.

3. Triangle ABC is isosceles, with base BC. Then

m∠ABC=m∠ACB.

From the previous you have that m∠ABC=65° (angle ABC is exactly angle CBD). So

m∠ACB=65°.

4. Angles BCD and DCA together form angle ACB. This gives you

m∠ACB=m∠ACD+m∠BCD,

m∠ACD=65°-50°=15°.

Have a good Day!

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tia_tia [17]

Answer:

Probability that deliberation will last between 12 and 15 hours is 0.1725.

Step-by-step explanation:

We are given that a recent study showed that the length of time that juries deliberate on a verdict for civil trials is normally distributed with a mean equal to 12.56 hours with a standard deviation of 6.7 hours.

<em>Let X = length of time that juries deliberate on a verdict for civil trials</em>

So, X ~ N( $\mu = 12.56, \sigma^{2} = 6.7^{2}$ )

The z score probability distribution is given by;

Z = $\frac{X-\mu}{\sigma}$ ~ N(0,1)

where, $\mu$ = mean time = 12.56 hours

$\sigma$ = standard deviation = 6.7 hours

So, Probability that deliberation will last between 12 and 15 hours is given by = P(12 hours < X < 15 hours) = P(X < 15) - P(X $\leq$ 12)

P(X < 15) = P( $\frac{X-\mu}{\sigma}$ < $\frac{15-12.56}{6.7}$ ) = P(Z < 0.36) = 0.64058

P(X $\leq$ 12) = P( $\frac{X-\mu}{\sigma}$ $\leq$ $\frac{12-12.56}{6.7}$ ) = P(Z $\leq$ -0.08) = 1 - P(Z < 0.08)

= 1 - 0.53188 = 0.46812

<em>Therefore, P(12 hours < X < 15 hours) = 0.64058 - 0.46812 = 0.1725</em>

Hence, probability that deliberation will last between 12 and 15 hours is 0.1725.

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3 years ago

Evaluate the following expressions: 2(−1 + 3) − 7

Svetach [21]

Answer:

-3 is the answer.

Step-by-step explanation:

=2(-1+3)-7

=2(2)-7

=4-7

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Hope it will help you :)

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3 years ago

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-------------------------------\\\\$

$\bf \boxed{5i+12j}\implies 
\begin{array}{rllll}
\ \textless \ 5&,&12\ \textgreater \ \\
x&&y
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\\\\\\
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\\\\\\
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if we were to place <5, 12> in standard position, so it'd be originating from 0,0, then the rise is 12 and the run is 5.

so any other vector that has a negative reciprocal slope to it, will then be perpendicular or "orthogonal" to it.

so... for example a parallel to <-12, 5> is say hmmm < -144, 60>, if you simplify that fraction, you'd end up with <-12, 5>, since all we did was multiply both coordinates by 12.

or using a unit vector for those above, then

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\\\\\\
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