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3 years ago

What is the solution to the system of equations? -2x + y = -5 3x – 2y = 12 A) (3, 1) B) (6, 3) C) (-2, -9) D) (-2, -1)

Mathematics

1 answer:

max2010maxim [7]3 years ago

6 0

Answer:

The correct answer is D) (-2, -1)

Step-by-step explanation:

In order to solve this system of equations, start by multiplying the entire first equation by 2. Then add the two equations together. This will get the y's to cancel and allow you to solve for x.

-4x + 2y = -10

3x - 2y = 12

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

-x = 2

x = -2

Now that we have the value for x, we can find y by plugging the x value into either equation.

-2x + y = -5

-2(2) + y = -5

-4 + y = -5

y = -1

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Advocard [28]

Answer:

161700 ways.

Step-by-step explanation:

The order in which the transistors are chosen is not important. This means that we use the combinations formula to solve this question.

Combinations formula:

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In this question:

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3 years ago

Using only words solve 8x+3=27 step by step

erik [133]

Answer:

X=3

Step-by-step explanation:

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5 0

3 years ago

Read 2 more answers

5) Find the equation of the line going through the point (4,1) and perpendicular to y = - 3x +7

vovangra [49]

Answer:

3y=x-1 OR y=⅓x-⅓

Step-by-step explanation:

Lets call the equation y=-3x+7 line l1

the other line passing through (4,1) l2

If two lines are perpendicular,then the product of their roots=-1

That is m(l1)×m(l2)=-1

Slope of l1=-3 therefore slope of l2=-1÷-3=⅓

Now that we have determined the slope of l2 we move on to find it's equation using the point-slope form

y-y1=m(x-x1)

y-1=⅓(x-4)

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3y=x-1 OR y=⅓x-⅓

6 0

3 years ago

Solve the following system of equations by the substitution method.

ruslelena [56]

5x = y + 6 (I)
2x - 3y = 4 (II)
-------------------
We have:
5x = y + 6 → $x = \frac{y+6}{5}$

Soon:
2x - 3y = 4 → $2* (\frac{y+6}{5}) - 3y = 4\to \frac{2y+12}{5} - 3y = 4$
least common multiple (5)
 $\frac{2y+12}{5} - 3y = 4\to \frac{2y+12}{\diagup\!\!\!\!\!5} - \frac{15y}{\diagup\!\!\!\!\!5} = \frac{20}{\diagup\!\!\!\!\!5}$
$2y + 12 - 15y = 20$
$- 15y + 2y = 20 - 12$
$- 13y = 8$
$\boxed{\boxed{y = - \frac{8}{13} }}\end{array}}\qquad\quad\checkmark$

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3 years ago

A group of workers can plant 5/8 acres in 4/5 days. What is the unit rate in acres per day?

Mila [183]

In order to find the unit rate of acres per day, or in other words, how many acres can they plant in one day, you must divide 5/8, the number of acres planted, by 4/5, the number of days it took to plant. When you divide the two fractions, first set up an expression:
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Then, to make things simpler, turn the division expression into a multiplication statement so that you have 5/8*5/4. Then multiply straight across and you get your answer as 25/32. This means that the workers can plant 25/32 acres per day.

3 0

3 years ago