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Masja [62]
3 years ago
11

Does anyone know how to do this ??? -view attachment

Mathematics
1 answer:
cricket20 [7]3 years ago
8 0

As soon as I read this, the words "law of cosines" popped
into my head.  I don't have a good intuitive feeling for the
law of cosines, but I went and looked it up (you probably
could have done that), and I found that it's exactly what
you need for this problem.

The "law of cosines" relates the lengths of the sides of any
triangle to the cosine of one of its angles ... just what we need,
since we know all the sides, and we want to find one of the angles.

To find angle-B, the law of cosines says

       b² = a² + c² - 2 a c cosine(B)

B  =  angle-B
b  =  the side opposite angle-B = 1.4
a, c = the other 2 sides = 1 and 1.9

                  (1.4)² = (1)² + (1.9)² - (2 x 1 x 1.9) cos(B)

                 1.96  =  (1) + (3.61)  -  (3.8) cos(B)

Add  3.8 cos(B)  from each side:

                 1.96 + 3.8 cos(B) = 4.61

Subtract  1.96  from each side:

                             3.8 cos(B) =  2.65

Divide each side by  3.8 :

                                  cos(B)  =  0.69737  (rounded)

Whipping out the
trusty calculator:
                                 B  = the angle whose cosine is 0.69737

                                      =  45.784° .

Now, for the first time, I'll take a deep breath, then hold it
while I look back at the question and see whether this is
anywhere near one of the choices ...

By gosh !  Choice 'B' is  45.8° !                    yay !
I'll bet that's it !

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Find the measure of ZB.
RoseWind [281]

The sum of the inside angles of a triangle, always sum up to 180 degrees. Using this information, we can create the following equation for this problem:

(3x-2)\text{ +(6}x\text{+11)+(5}x\text{ +3) = 180}

Adding up all terms with 'x' and adding the other together, we have the following equation:

\begin{gathered} (3x+6x+5x)+(11+3-2)=180_{} \\ 14x+12=180 \\ 14x=180-12=168 \end{gathered}

Solving this last equation for 'x', we have the following:

\begin{gathered} 14x=168 \\ x=\frac{168}{14}=12 \end{gathered}

Then, the final answer for the 'x' value is twelve!

6 0
8 months ago
Marcy owed her frien Ericka $25 dollars and owed her $15 dollars.
padilas [110]
She owes in total 40$ in total but seprate
6 0
3 years ago
Each morning Rin rides 1.5 miles to school and then rides home in the afternoon. Later in the evening, she rides to the park and
brilliants [131]

Answer:

Last equation given in the list of possible answers:

5 ( 1.5 + 1.5 + x ) = 25

Step-by-step explanation:

We need to include in the total addition of miles ridden during the week:

a) 1.5 miles to the school

b) 1.5 miles from school back home

c) x miles for the evening ride

so for the miles ridden per day we have: "1.5 +1.5 + x"

Now, since per week she does 5 days like this, then we need to multiply the expression above by 5 in order to total the number of miles she rides weekly (25 miles)

5 ( 1.5 + 1.5 + x ) = 25

And we can use this equation to find the amount "x" that Rin rides in the evening.

7 0
3 years ago
Which is bigger 5/8 or 7/12
gladu [14]
5/8=0.625

7/12=0.583......

5/8 is bigger as ive put both into a decimal as it is easier to tell
4 0
3 years ago
Read 2 more answers
Round 83.13 to the nearest dollar
kvv77 [185]
It would be $83.00 kid
Have a nice day!!!
5 0
3 years ago
Read 2 more answers
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