All categories

3 years ago

Solving a right triangle (ROUND TO THE NEAREST TENTH)

Mathematics

1 answer:

Kay [80]3 years ago

3 0

Answer:

see explanation

Step-by-step explanation:

The sum of the 3 angles in a triangle = 180°

Subtract the sum of the given angles from 180 for B

B = 180° - (90 + 40)° = 180° - 130° = 150°

--------------------------------------------------------------

sin40° = $\frac{opposite}{hypotenuse}$ = $\frac{a}{21}$

Multiply both sides by 21

21 × sin40° = a, thus

a ≈ 13.5 ( to the nearest tenth )

--------------------------------------------------------------

cos40° = $\frac{adjacent}{hypotenuse}$ = $\frac{b}{21}$

Multiply both sides by 21

21 × cos40° = b, thus

b ≈ 16.1 ( to the nearest tenth )

You might be interested in

There are 25 students in a class. 16 of those students are boys. What percent of the class are girls?

fomenos

Answer:

36 %

Step-by-step explanation:

9 girls = 36%

25 students = 100

7 0

3 years ago

Read 2 more answers

The following graph shows the time required to braid a necklace based on its length? Which statements about the graph are true?

sdas [7]

Answer:

The answer would be A and B

Step-by-step explanation:

I really did not have an explanation because I found out by guessing because I did not understand. :)

5 0

3 years ago

A rectangular piece of metal is 25 in longer than it is wide. Squares with sides 5 in long are cut from the four corners and the

Licemer1 [7]

Answer:

The original length was 41 inches and the original width was 16 inches

Step-by-step explanation:

Let

x ----> the original length of the piece of metal

y ----> the original width of the piece of metal

we know that

When squares with sides 5 in long are cut from the four corners and the flaps are folded upward to form an open box

The dimensions of the box are

$L=(x-10)\ in\\W=(y-10)\ in\\H=5\ in$

The volume of the box is equal to

$V=(x-10)(y-10)5$

$V=930\ in^3$

$930=(x-10)(y-10)5$

simplify

$186=(x-10)(y-10)$ -----> equation A

Remember that

The piece of metal is 25 in longer than it is wide

$x=y+25$ ----> equation B

substitute equation B in equation A

$186=(y+25-10)(y-10)$

solve for y

$186=(y+15)(y-10)\\186=y^2-10y+15y-150\\y^2+5y-336=0$

Solve the quadratic equation by graphing

using a graphing tool

The solution is y=16

see the attached figure

Find the value of x

$x=16+25=41$

therefore

The original length was 41 inches and the original width was 16 inches

3 0

3 years ago

Alex made an eyeglass case and sold it for $12.00. He spent $1.29 on felt and $2.75 on a needle and thread. What was his profit?

madreJ [45]

D because 1.29 plus 2.75 is 4.04(the money that he used to make the case) and subtract that with $12 and you get $7.96 as the profit.

5 0

3 years ago

Read 2 more answers

The number of years of education of self-employed individuals in the united states has a population mean of 13.6 years and a pop

muminat

Answer:

0.3 years

Step-by-step explanation:

With problems like these, I always like to start by breaking down the information into smaller pieces.

μ = 13.6

σ = 3.0

Survey of 100 self-employed people

(random variable) X = # of years of education

So now we have some notation, where μ represents population mean and σ represents population standard deviation. Hopefully, you already know that the sample mean of x-bar is the same as the population mean, so x-bar = 13.6. Now, the question asks us what the standard deviation is. Since the sample here is random, we can use the Central Limit Theorem, which allows us to guess that a distribution will be approximately normal for large sample sizes (that is, n ≥ 30). In this case, our sample size is 100, so that is satisfied. We're also told our sample is random, so we're good there, too. Now all we have to do is plug some stuff in.

The Central Limit Theorem says that for large values of n, x-bar follows an approximately normal distribution with sample mean = μ and sample standard deviation = σ/√n. So, with that info, all we need to do to find the standard deviation of x-bar is to plug our σ and n into the above formula.

σ(x-bar) = σ/√n

σ(x-bar) = 3.0/√100

σ(x-bar) = 0.3

So your answer here is .3 years.

7 0

3 years ago