-26a-19-35=-84 . show work!!

Calculate the area of quadrilateral ABCD. State the units of your answer.

cluponka [151]

Answer:

158.76 cm²

Step-by-step explanation:

Quadrilateral ABCD is composed of 2 right triangles

Construct the line BD, then

Δ ABD and Δ BCD are the 2 right triangles.

The area (A) of a triangle is calculated using

A = $\frac{1}{2}$ bh ( b is the base and h the perpendicular height )

Δ ABD with b = 18 and h = 7.5

A = $\frac{1}{2}$ × 18 × 7.5 = 9 × 7.5 = 67.5 cm²

Δ BCD with b = 15.6 and h = 11.7

A = $\frac{1}{2}$ × 15.6 × 11.7 = 7.8 × 11.7 = 91.26 cm²

Thus

area of ABCD = 67.5 + 91.26 = 158.76 cm²

3 0

3 years ago

K ÷1 3 =10 what is the answer to the equation?

adell [148]

this the answer K=130

7 0

3 years ago

Read 2 more answers

A business breaks even when the production costs are equal to the revenue. The expression 120+4x represents the cost of producin

nika2105 [10]

Answer:

Results are below.

Step-by-step explanation:

Giving the following information:

The expression 120+4x represents the cost of producing x items. The selling price is $5 for each item.

The net income formula:

y= (5 - 4)x - 120

(5-4)= contribution margin per unit sold (x)

120= fixed costs

To calculate the break-even point in units, we need to use the following formula:

Break-even point in units= fixed costs/ contribution margin per unit

Break-even point in units= 120 / 1

Break-even point in units= 120 units

Prove:

y= 1*120 - 120

y= 0

5 0

3 years ago

In a sample of nequals16 lichen specimens, the researchers found the mean and standard deviation of the amount of the radioacti

GuDViN [60]

Answer:

(a) The confidence level desired by the researchers is 95%.

(b) The sampling error is 0.002 microcurie per millilitre.

(c) The sample size necessary to obtain the desired estimate is 25.

Step-by-step explanation:

The mean and standard deviation of the amount of the radioactive element, cesium-137 present in a sample of n = 16 lichen specimen are:

$\bar x=0.009\\s=0.005$

Now it is provided that the researchers want to increase the sample size in order to estimate the mean μ to within 0.002 microcurie per millilitre of its true value, using a 95% confidence interval.

The (1 - α)% confidence interval for population mean (μ) is:

$CI=\bar x\pm z_{\alpha/2}\times \frac{s}{\sqrt{n}}$

(a)

The confidence level is the probability that a particular value of the parameter under study falls within a specific interval of values.

In this case the researches wants to estimate the mean using the 95% confidence interval.

Thus, the confidence level desired by the researchers is 95%.

(b)

In case of statistical analysis, during the computation of a certain statistic, to estimate the value of the parameter under study, certain error occurs which are known as the sampling error.

In case of the estimate of parameter using a confidence interval the sampling error is known as the margin of error.

In this case the margin of error is 0.002 microcurie per millilitre.

(c)

The margin of error is computed using the formula:

$MOE=z_{\alpha/2}\times \frac{s}{\sqrt{n}}$