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4 years ago

The base of a triangle is seven less than twice its height. If the area of the triangle is 100cm^2 find the length of the base

Mathematics

2 answers:

shusha [124]4 years ago

8 0

Okay i got lets work itAnswer:

h≈4.874 cm,b≈21.748 cm

Explanation:

Atriangle=12bh

"The base of a triangle is twelve more than twice its height."

From this we can say that:

b=2h+12

So, if A=12bh, we can replace b with 2h+12.

A=12(2h+12)h

53=12(2h+12)h

53=(h+6)h

53=h2+6h

h2+6h−53=0

Use the quadratic formula.

h=−6±√62−4(−53)(1)2

h≈4.874

(Ignore the negative answer—height can't be negative.)

b≈2(4.874)+12

b≈21.748

Alexeev081 [22]4 years ago

7 0

2x-7 * x
----------- =. 100^2= 10000
2

2x^2-7/2= x^2-7/2

x^2-7/2=10000

x^2 = 20007/7

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3 years ago

A researcher working in a Human Resources department was interested in gender and sales figures so he conducted a t-test. The me

irina1246 [14]

Answer:

$d = \frac{78.24 -66.25}{\sqrt{\frac{7^2 +7^2}{2}}}= 1.713$

For the interpretation we consider a value for d small is is between 0-0.2, medium if is between 0.2-0.8 and large if is higher than 0.8.

And on this case 1.713>0.8 so we have a large effect size

This value of d=1.713 are telling to us that the two groups differ by 1.713 standard deviation and we will have a significant difference between the two means.

Step-by-step explanation:

Previous concepts

The Effect size is a "quantitative measure of the magnitude of the experimenter effect. "

The Cohen's d effect size is given by the following formula:

$d = \frac{\bar X_1 -\bar X_2}{\sqrt{\frac{s^2_1 +s^2_2}{2}}}$

Solution to the problem

And for this case we can assume:

$\bar X_1 =78.24$ the mean for females

$\bar X_2 =66.25$ the mean for males

$s_1 = s_2= 7$ represent the deviations for both groups

And if we replace we got:

$d = \frac{78.24 -66.25}{\sqrt{\frac{7^2 +7^2}{2}}}= 1.713$

For the interpretation we consider a value for d small is is between 0-0.2, medium if is between 0.2-0.8 and large if is higher than 0.8.

And on this case 1.713>0.8 so we have a large effect size

This value of d=1.713 are telling to us that the two groups differ by 1.713 standard deviation and we will have a significant difference between the two means.

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