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3 years ago

WILL GIVE BRAINLIEST. If 3x+5y=13 and 6x+7y=20, find the value of y/x

Mathematics

2 answers:

Illusion [34]3 years ago

8 0

Answer:

X = 1

Y = 2

Step-by-step explanation:

3x+5y=13

3(1)+5(2)=13

3+10

6x+7y=20

6(1)+7(2)=20

6+14

Scilla [17]3 years ago

3 0

Answer:

y= 2 x=1

Step-by-step explanation:

You may use the substitution or even the elimination method. Hoped that helped ;)

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If (6^2]^p = 6^10, what is the value of p? A.) 2 B.) 3 C.) 4 D.) 5

kvv77 [185]

If u raise a power to another power, then u multiply the powers. In this case, u can simplify to 6^2p =6^10

Now you have like bases, so you can set the powers equal to each other. So now, 2p=10. Now p=5

5 0

3 years ago

In a right triangle ABC, CD is an altitude, such that AD=BC. Find AC, if AB=3 cm, and CD= 2 cm.

konstantin123 [22]

Consider right triangle ΔABC with legs AC and BC and hypotenuse AB. Draw the altitude CD.

1. Theorem: The length of each leg of a right triangle is the geometric mean of the length of the hypotenuse and the length of the segment of the hypotenuse adjacent to that leg.

According to this theorem,

$BC^2=BD\cdot AB.$

Let BC=x cm, then AD=BC=x cm and BD=AB-AD=3-x cm. Then

$x^2=(3-x)\cdot 3,\\ \\x^2=9-3x,\\ \\x^2+3x-9=0,\\ \\D=3^2-4\cdot (-9)=9+36=45,\\ \\\sqrt{D}=\sqrt{45}=3\sqrt{5},\\ \\x_1=\dfrac{-3-3\sqrt{5} }{2}0.$

Take positive value x. You get

$AD=BC=\dfrac{-3+3\sqrt{5} }{2}\ cm.$

2. According to the previous theorem,

$AC^2=AD\cdot AB.$

Then

$AC^2=\dfrac{-3+3\sqrt{5} }{2}\cdot 3=\dfrac{-9+9\sqrt{5} }{2},\\ \\AC=\sqrt{\dfrac{-9+9\sqrt{5} }{2}}\ cm.$

Answer: $AC=\sqrt{\dfrac{-9+9\sqrt{5} }{2}}\ cm.$

This solution doesn't need CD=2 cm. Note that if AB=3cm and CD=2cm, then

$CD^2=AD\cdot DB,\\ \\2^2=AD\cdot (3-AD),\\ \\AD^2-3AD+4=0,\\ \\D$

This means that you cannot find solutions of this equation. Then CD≠2 cm.

8 0

3 years ago

Read 2 more answers

A sociologist wants to determine if the life expectancy of people in africa is less than the life expectancy of people in asia.

Colt1911 [192]

Answer:

The sample statistics are attached.

First, we need to determine the hypothesis.

The null hypothesis should be: $H_{o} : u_{africa} \geq u_{asia}$ .

The alternative hypothesis should be: $H_{a}: u_{africa}$

The next step is about calculating the t statistics based on the samples. This t test will give the probability value or p-value, which determines if there's enough to reject the null hypothesis. The formula we need to use to find the t-value is: $t=\frac{x_{1}-x_{2} }{\sqrt{\frac{s_{1} ^{2} }{n_{1} } +\frac{s_{2} ^{2} }{n_{2} } } }$

Replacing all the values into the formula, we have:

$t=\frac{52.4-58.1}{\sqrt{\frac{(7.4)^{2} }{45}+\frac{(8.8)^{2} }{35} } } \\t=\frac{-5.7}{\sqrt{1.2+2.2} } =\frac{-5.7}{1.8} =-3.2$

Therefore, the t-value is -3.2.

Now, we using a level of significance of 0.01, and a degree of freedom (df) of 34, we use the t-table to find the p-value for this results. (df = N -1; in this case, we take the smaller sample, which is 35, giving us 34 of df).

Therefore, according to the table attached, the p-value is less than 0.01, which is less than our level of significance. This result means that the null hypothesis is rejected. In other words, there's enough evidence to say that the life expectancy of people in Africa is less than the life of expectancy of people in Asia.

3 0

3 years ago

M_6 is (2x - 5)º and m_8 is (x + 5)º. What is m 3?

oksano4ka [1.4K]

m_3 is (7x-4)°

Step-by-step explanation:

which is that m_3 is(7x -4)°.

3 0

3 years ago

Helppp Plsss Asap!!! Thanks

tester [92]

Answer:

Step-by-step explanation:

The average rate of change is

f(x2) - f(x1)

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

x2-x1

We want to find the change from 1 to 3

f(3) = 8

f(1) = 2

f(3) - f(1) 8-2 6

----------------- = ------------ = ---- = 3

3-1 2 2

4 0

3 years ago