1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Setler79 [48]
2 years ago
8

What is the area of the triangle? Use the formula: Area of a triangle = 1/2bh.How do you find the area of a triangle?

Mathematics
1 answer:
velikii [3]2 years ago
4 0

9514 1404 393

Answer:

  4 square inches

Step-by-step explanation:

The only triangle in the figure is 4 in wide and 2 in high. Using these values in the given formula, we find the area to be ...

  A = 1/2bh

  A = (1/2)(4 in)(2 in) = 4 in²

The area of the triangle is 4 square inches.

You might be interested in
Find equations of the spheres with center(3, −4, 5) that touch the following planes.a. xy-plane b. yz- plane c. xz-plane
postnew [5]

Answer:

(a) (x - 3)² + (y + 4)² + (z - 5)² = 25

(b) (x - 3)² + (y + 4)² + (z - 5)² = 9

(c) (x - 3)² + (y + 4)² + (z - 5)² = 16

Step-by-step explanation:

The equation of a sphere is given by:

(x - x₀)² + (y - y₀)² + (z - z₀)² = r²            ---------------(i)

Where;

(x₀, y₀, z₀) is the center of the sphere

r is the radius of the sphere

Given:

Sphere centered at (3, -4, 5)

=> (x₀, y₀, z₀) = (3, -4, 5)

(a) To get the equation of the sphere when it touches the xy-plane, we do the following:

i.  Since the sphere touches the xy-plane, it means the z-component of its centre is 0.

Therefore, we have the sphere now centered at (3, -4, 0).

Using the distance formula, we can get the distance d, between the initial points (3, -4, 5) and the new points (3, -4, 0) as follows;

d = \sqrt{(3-3)^2+ (-4 - (-4))^2 + (0-5)^2}

d = \sqrt{(3-3)^2+ (-4 + 4)^2 + (0-5)^2}

d = \sqrt{(0)^2+ (0)^2 + (-5)^2}

d = \sqrt{(25)}

d = 5

This distance is the radius of the sphere at that point. i.e r = 5

Now substitute this value r = 5 into the general equation of a sphere given in equation (i) above as follows;

(x - 3)² + (y - (-4))² + (z - 5)² = 5²  

(x - 3)² + (y + 4)² + (z - 5)² = 25  

Therefore, the equation of the sphere when it touches the xy plane is:

(x - 3)² + (y + 4)² + (z - 5)² = 25  

(b) To get the equation of the sphere when it touches the yz-plane, we do the following:

i.  Since the sphere touches the yz-plane, it means the x-component of its centre is 0.

Therefore, we have the sphere now centered at (0, -4, 5).

Using the distance formula, we can get the distance d, between the initial points (3, -4, 5) and the new points (0, -4, 5) as follows;

d = \sqrt{(0-3)^2+ (-4 - (-4))^2 + (5-5)^2}

d = \sqrt{(-3)^2+ (-4 + 4)^2 + (5-5)^2}

d = \sqrt{(-3)^2 + (0)^2+ (0)^2}

d = \sqrt{(9)}

d = 3

This distance is the radius of the sphere at that point. i.e r = 3

Now substitute this value r = 3 into the general equation of a sphere given in equation (i) above as follows;

(x - 3)² + (y - (-4))² + (z - 5)² = 3²  

(x - 3)² + (y + 4)² + (z - 5)² = 9  

Therefore, the equation of the sphere when it touches the yz plane is:

(x - 3)² + (y + 4)² + (z - 5)² = 9  

(b) To get the equation of the sphere when it touches the xz-plane, we do the following:

i.  Since the sphere touches the xz-plane, it means the y-component of its centre is 0.

Therefore, we have the sphere now centered at (3, 0, 5).

Using the distance formula, we can get the distance d, between the initial points (3, -4, 5) and the new points (3, 0, 5) as follows;

d = \sqrt{(3-3)^2+ (0 - (-4))^2 + (5-5)^2}

d = \sqrt{(3-3)^2+ (0+4)^2 + (5-5)^2}

d = \sqrt{(0)^2 + (4)^2+ (0)^2}

d = \sqrt{(16)}

d = 4

This distance is the radius of the sphere at that point. i.e r = 4

Now substitute this value r = 4 into the general equation of a sphere given in equation (i) above as follows;

(x - 3)² + (y - (-4))² + (z - 5)² = 4²  

(x - 3)² + (y + 4)² + (z - 5)² = 16  

Therefore, the equation of the sphere when it touches the xz plane is:

(x - 3)² + (y + 4)² + (z - 5)² = 16

 

3 0
3 years ago
Suppose that a researcher is designing a survey to estimate the proportion of adults in your state who oppose a proposed law tha
irinina [24]

Answer:

n=\frac{0.5 (1-0.5)}{(\frac{0.02}{1.96})^2}= 2401

So without prior estimation for the population proportion, using a confidence level of 95% if we want a margin of error about 2% we need al least a sample size of 2401.

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".  

The margin of error is the range of values below and above the sample statistic in a confidence interval.  

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".  

The population proportion have the following distribution  

p \sim N(p,\sqrt{\frac{\hat p(1-\hat p)}{n}})  

Solution to the problem

The margin of error for the proportion interval is given by this formula:  

ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}} (a)  

If solve n from equation (a) we got:  

n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2} (b)  

The margin of error desired for this case is ME= \pm 0.02 equivalent to 2% points

For this case we need to assume a confidence level, let's assume 95%. And since we don't have prior estimation for the population proportion of interest the best value to do an approximation is \hat p =0.5

In order to find the critical value we need to take in count that we are finding the margin of error for a proportion, so on this case we need to use the z distribution. Since our interval is at 95% of confidence, our significance level would be given by \alpha=1-0.95=0.05 and \alpha/2 =0.025. And the critical value would be given by:  

z_{\alpha/2}=\pm 1.96  

Now we have all the values needed and if we replace into equation (b) we got:

n=\frac{0.5 (1-0.5)}{(\frac{0.02}{1.96})^2}= 2401

So without prior estimation for the population proportion, using a confidence level of 95% if we want a margin of error about 2% we need al least a sample size of 2401.

5 0
3 years ago
Each salt shaker holds 1 1/4 ounces. If a box of salt contains 10 ounces, how many shakers will it fit
Alekssandra [29.7K]
8 shakers will fit  becuase 4 shakers equal 5 ounces and you multiply it by two and you get 10

3 0
3 years ago
Read 2 more answers
Mrs. Morton has a special reward system for her class. When all her students behave well, she rewarded him by putting 3 marbles
Law Incorporation [45]
Needs 76 more marbles
7 0
3 years ago
What constant acceleration is needed to accelerate a baseball from 6 feet/sec to 116 feet/sec in 2 seconds?
Vesnalui [34]

Answer:

  d. 55 feet /sec^2

Step-by-step explanation:

Average acceleration is ...

  a = ∆v/∆t = (116 ft/s -6 ft/s)/(2 s)

  = 110/2 ft/s^2 = 55 ft/s^2

4 0
2 years ago
Other questions:
  • What is 18/2 expressed as a whole or mixed number
    12·1 answer
  • What is the solution set?
    14·1 answer
  • Is it true yes or no
    7·2 answers
  • PLEASE HELP!!!
    7·1 answer
  • The triangle shown here appears to be, A) acute.
    9·2 answers
  • What is the product of 8/15 times 6/5 and 1/3
    7·2 answers
  • .
    15·2 answers
  • On a map 1 cm = 50 mi. On the map, Grand Canyon is 4 cm from Phoenix. What is the actual distance?
    12·1 answer
  • Write and solve an equation to find the value of x. Show your work.
    10·1 answer
  • If the train from Milan, Italy, to Rome, Italy, takes 6 hours at a speed of 130 miles per hour, how many miles from Milan is Rom
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!