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3 years ago

PLEASE ANSWERRRRRRRRRR

Mathematics

1 answer:

mash [69]3 years ago

8 0

Answer: OPTION B.

Step-by-step explanation:

Given the following System of equations:

$\left \{ {{3x-5y=19} \atop {x+y=1}} \right.$

You can use the Elimination Method to solve it. The steps are:

1. You can mutliply the second equation by -3.

2. Then you must add the equations.

3. Solve for the variable "y".

Then:

$\left \{ {{3x-5y=19} \atop {-3x-3y=-3}} \right.\\.....................\\-8y=16\\\\y=\frac{16}{-8}\\\\y=-2$

4. Now that you know the value of the variable "y", you must substitute it into any original equation.

5. The final step is to solve for "x" in order to find its value.

Then:

$x+(-2)=1\\\\x=1+2\\\\x=3$

Therefore, the solution is:

$(3,-2)$

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Can anyone help please?

katen-ka-za [31]

Answer:

A'(-3, 12)
B'(9, 6)
C'(-6, -6)

Step-by-step explanation:

Dilation about the origin multiplies each coordinate value by the dilation factor.

For dilation factor k, the new coordinates are ...

(x, y) ⇒ (kx, ky)

Your dilation factor is 3, so the transformation is ...

(x, y) ⇒ (3x, 3y)

A(-1, 4) ⇒ A'(-3, 12)

B(3, 2) ⇒ B'(9, 6)

C(-2, -2) ⇒ C'(-6, -6)

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2 years ago

Need help tremendously

Alina [70]

<span>basically since 30 minutes is half of an hour, to get to a full hour you can multiply by 2, so you do that for both, 2/3 included so you get 2/3 * 2/1 4/3 is 1 1/3</span>

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3 years ago

Simplify <br><br><img src="https://tex.z-dn.net/?f=%28x%5E%7B2%7D%20%20%2B%203x%20-%204%29%20%2B%20%284%5E%7B2%7D%20%20-%205%29%

xxTIMURxx [149]

X^2-4x+4 is the answer, to save you points next time, use an app called M8thw8y

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3 years ago

Read 2 more answers

A rectangle initially has dimensions 6 cm by 7 cm. All sides begin increasing in length at a rate of 1 cm/s. At what rate is the

Morgarella [4.7K]

Answer:

49 cm²/s

Step-by-step explanation:

The problem statement tells you what to do.

Write an equation relating A, b, h:

A = bh . . . . . . the equation for the area of a rectangle

Differentiate with respect to t:

dA/dt = (db/dt)h + b(dh/dt) . . . . . . . product rule

To find the rate of change after 18 seconds, you need to know the dimensions b and h after 18 seconds. Since each dimension was increasing at the rate of 1 cm/s, it is 18 cm more than it was at the beginning:

At 18 seconds,

b = 6 cm + 18 cm = 24 cm;

h = 7 cm + 18 cm = 25 cm.

Of course, db/dt = dh/dt = 1 cm/s. Then the rate of change of area is ...

dA/dt = (1 cm/s)(25 cm) + (24 cm)(1 cm/s)

dA/dt = 49 cm²/s

_____

You could write a formula for the area as a function of time and differentiate that:

A = (6 +t)(7 +t) = 42 + 13t + t²

Then the derivative is ...

dA/dt = 13 +2t

and when t=18, this is ...

dA/dt = 13 + 2(18) = 49 . . . . cm²/s

7 0

3 years ago

Jack wants to know how many families in his small neighborhood of 60 homes would help organize a neighborhood fund-raising party

seraphim [82]

hello,

Jack wants to know how many families in his small neighborhood of 60 homes would help organize a neighborhood fund-raising party. He put all the addresses in a bag and drew a random sample of 30 addresses. He then asked those families if they would help organize the fund-raising party. He found that 12% of the families would help organize the party. He claims that 12% of the neighborhood families would be expected to help organize the party. Is this a valid inference?

Yes, this is a valid inference because the 30 families speak for the whole neighborhood

it's the correct one because if he ask 30 families so they talk to their neighborhood so its will be 60 ;) so its correct,

hope this help

7 0

3 years ago