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3 years ago

X + 2y = 5 x - 3y = 7 What is the value of the y-determinant? -2 -1 2

Mathematics

1 answer:

grandymaker [24]3 years ago

5 0

Answer:

y-determinant = 2

Step-by-step explanation:

Given the following system of equation:

x + 2y = 5
x - 3y = 7

Let's represent it using a matrix:

$\left[\begin{array}{ccc}1&2\\1&-3\end{array}\right] = \left[\begin{array}{ccc}5\\7\end{array}\right]$

The y‐numerator determinant is formed by taking the constant terms from the system and placing them in the y‐coefficient positions and retaining the x‐coefficients. Then:

$\left[\begin{array}{ccc}1&5\\1&7\end{array}\right]$

y-determinant = (1)(7) - (5)(1) = 2.

Therefore, the y-determinant = 2

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A sales manager gathered information on the number of sales calls made and the number of copiers sold for a random sample of 20

lubasha [3.4K]

Answer:

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2 years ago

HELP! Find the value of sin 0 if tan 0 = 4; 180 < 0< 270

BabaBlast [244]

Hi there! Use the following identities below to help with your problem.

$\large \boxed{sin \theta = tan \theta cos \theta} \\ \large \boxed{tan^{2} \theta + 1 = {sec}^{2} \theta}$

What we know is our tangent value. We are going to use the tan²θ+1 = sec²θ to find the value of cosθ. Substitute tanθ = 4 in the second identity.

$\large{ {4}^{2} + 1 = {sec}^{2} \theta } \\ \large{16 + 1 = {sec}^{2} \theta } \\ \large{ {sec}^{2} \theta = 17}$

As we know, sec²θ = 1/cos²θ.

$\large \boxed{sec \theta = \frac{1}{cos \theta} } \\ \large \boxed{ {sec}^{2} \theta = \frac{1}{ {cos}^{2} \theta} }$

And thus,

$\large{ {cos}^{2} \theta = \frac{1}{17}} \\ \large{cos \theta = \frac{ \sqrt{1} }{ \sqrt{17} } } \\ \large{cos \theta = \frac{1}{ \sqrt{17} } \longrightarrow \frac{ \sqrt{17} }{17} }$

Since the given domain is 180° < θ < 360°. Thus, the cosθ < 0.

$\large{cos \theta = \cancel\frac{ \sqrt{17} }{17} \longrightarrow cos \theta = - \frac{ \sqrt{17} }{17}}$

Then use the Identity of sinθ = tanθcosθ to find the sinθ.

$\large{sin \theta = 4 \times ( - \frac{ \sqrt{17} }{17}) } \\ \large{sin \theta = - \frac{4 \sqrt{17} }{17} }$

Answer

sinθ = -4sqrt(17)/17 or A choice.

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3 years ago

System of equations<br><br>y=1/2x +5<br>y=3x -5

Art [367]

Answer: 4

Step-by-step explanation:

Set them equal to each other since they're both equal to y

3x-5=.5x +5

add 5 to both sides

3x=.5x+10

subtract .5x from both sides

2.5x=10

divide both sides by 2.5

x= 4

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2 years ago

a 240 centimeter board is to be cut into two pieces so that the longer piece is twice as long as the shorter piece. find the len

amid [387]

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so smaller piece/ x= 60
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3 years ago

Read 2 more answers

If you were given the function y=4x-3 and you had to find the Range, given the Domain: (1,3,5,7)

AysviL [449]

Answer:

option 4

Step-by-step explanation:

y = 4x-3

y = 4(1)-3

y = 1

y = 4(3)-3

y = 9

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y = 17

y = 4(7)-3

y = 25

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2 years ago