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2 years ago

Which lines are perpendicular to the line y - 1 = 1/3 (x+2)? Check all that apply.

Mathematics

1 answer:

ioda2 years ago

7 0

Answer: Options 1, 3, 5

Step-by-step explanation:

Perpendicular lines have slopes that are negative reciprocals, so since the slope of the given line is 1/3, we need to find lines with a slope of -3.

Option 1 has a slope of -3.
Option 2 has a slope of 3.
Option 3 has a slope of -3.
Option 4 has a slope of 1/3.
If we subtract 3x from both sides, we get y=-3x+7, so option 5 has a slope of -3.

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T-test Statistics

vitfil [10]

Answer:

976thousand

Step-by-step explanation:

6 0

3 years ago

I need help with questions #7 and #8 plz

katen-ka-za [31]

Answer:

7. A = 40.8 deg; B = 60.6 deg; C = 78.6 deg

8. A = 20.7 deg; B = 127.2 deg; C = 32.1 deg

Step-by-step explanation:

Law of Cosines

$c^2 = a^2 + b^2 - 2ab \cos C$

You know the lengths of the sides, so you know a, b, and c. You can use the law of cosines to find C, the measure of angle C.

Then you can use the law of cosines again for each of the other angles. An easier way to solve for angles A and B is, after solving for C with the law of cosines, solve for either A or B with the law of sines and solve for the last angle by the fact that the sum of the measures of the angles of a triangle is 180 deg.

We use the law of cosines to find C.

$18^2 = 12^2 + 16^2 - 2(12)(16) \cos C$

$324 = 144 + 256 - 384 \cos C$

$-384 \cos C = -76$

$\cos C = 0.2$

$C = \cos^{-1} 0.2$

$C = 78.6^\circ$

Now we use the law of sines to find angle A.

Law of Sines

$\dfrac{a}{\sin A} = \dfrac{b}{\sin B} = \dfrac{c}{\sin C}$

We know c and C. We can solve for a.

$\dfrac{a}{\sin A} = \dfrac{c}{\sin C}$

$\dfrac{12}{\sin A} = \dfrac{18}{\sin 78.6^\circ}$

Cross multiply.

$18 \sin A = 12 \sin 78.6^\circ$

$\sin A = \dfrac{12 \sin 78.6^\circ}{18}$

$\sin A = 0.6535$

$A = \sin^{-1} 0.6535$

$A = 40.8^\circ$

To find B, we use

m<A + m<B + m<C = 180

40.8 + m<B + 78.6 = 180

m<B = 60.6 deg

I'll use the law of cosines 3 times here to solve for all the angles.

Law of Cosines

$a^2 = b^2 + c^2 - 2bc \cos A$

$b^2 = a^2 + c^2 - 2ac \cos B$

$c^2 = a^2 + b^2 - 2ab \cos C$

Find angle A:

$a^2 = b^2 + c^2 - 2bc \cos A$

$8^2 = 18^2 + 12^2 - 2(18)(12) \cos A$

$64 = 468 - 432 \cos A$

$\cos A = 0.9352$

$A = 20.7^\circ$

Find angle B:

$b^2 = a^2 + c^2 - 2ac \cos B$

$18^2 = 8^2 + 12^2 - 2(8)(12) \cos B$

$324 = 208 - 192 \cos A$

$\cos B = -0.6042$

$B = 127.2^\circ$

Find angle C:

$c^2 = a^2 + b^2 - 2ab \cos C$

$12^2 = 8^2 + 18^2 - 2(8)(18) \cos B$

$144 = 388 - 288 \cos A$

$\cos C = 0.8472$

$C = 32.1^\circ$

8 0

3 years ago

What is 940 divided by 58 please help I'm doing my brothers homework xD

erica [24]

16 with the remainder 2

3 0

3 years ago

Read 2 more answers

What is the equation of the line shown in this graph? <br><br> The points are (-2, 2) and (-2, -3)

KengaRu [80]

$\bf (\stackrel{x_1}{-2}~,~\stackrel{y_1}{2})\qquad (\stackrel{x_2}{-2}~,~\stackrel{y_2}{-3}) \\\\\\ slope = m\implies \cfrac{\stackrel{rise}{ y_2- y_1}}{\stackrel{run}{ x_2- x_1}}\implies \cfrac{-3-2}{-2-(-2)}\implies \cfrac{-3-2}{-2+2}\implies \stackrel{und efined}{\cfrac{-5}{0}}$

so our slope is undefined, that means a vertical line, check the picture below

5 0

3 years ago

A lawyer charges for her services based on the number of hours worked. The expression gives the total cost for h hours is 200h+2

zhannawk [14.2K]

H is the number of hours worked. So the expression 200h+250 is 200 times the number of hours plus 250.

Here's a few computations using different values for h

1 hour --> (200)(1)+250 = 450
2 hours --> (200)(2) + 250 = 650
3 hours --> (200)(3)+250 = 850
10 hours --> (200)(10)+250 = 2250

As you can see the 250 is fixed. It gets added to the cost no matter how many hours the lawyer works. This is most likely a flat fee. Just to meet the lawyer you pay $250.

The 200 gets multiplied by the hours worked. So the 200 is an hourly rate. The more hours the lawyer works, the more he gets paid because this part of the expression depends on the hours worked.

Thus, an interpretation of the expression 200h + 250 is that the lawyer charges a fee of $250 per consultation and an additional $200 per hour on top of that.

4 0

4 years ago