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3 years ago

Question 24 Multiple Choice Worth 1 points)

Mathematics

1 answer:

hammer [34]3 years ago

8 0

Given:

The system of equations is:

Line A: $y=x-4$

Line B: $y=3x+4$

To find:

The solution of given system of equations.

Solution:

We have,

$y=x-4$ ...(i)

$y=3x+4$ ...(ii)

Equating (i) and (ii), we get

$x-4=3x+4$

$-4-4=3x-x$

$-8=2x$

Divide both sides by 2.

$-4=x$

Substituting $x=-4$ in (i), we get

$y=-4-4$

$y=-8$

The solution of system of equations is (-4,-8).

Now verify the solution by substituting $x=-4, y=-8$ in the given equations.

$-8=-4-4$

$-8=-8$

This statement is true.

Similarly,

$-8=3(-4)+4$

$-8=-12+4$

$-8=-8$

This statement is also true.

Therefore, (-4,-8) is a solution of the given system of equations, because the point satisfies both equations. Hence, the correct option is C.

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Answer:

she needs 3 3/4 yards more to make a quilt

Step-by-step explanation:

Total cloth needed = 10 1/2 yards

she has a total of = 2 1/2 + 4 1/4

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=6 + 2+1/4

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3 years ago

The following represents the probability distribution for the daily demand of microcomputers at a local store. Demand Probabilit

konstantin123 [22]

Answer:

The correct answer is 2.2.

Step-by-step explanation:

The following represents the probability distribution for the daily demand of microcomputers at a local store:

Demand Probability

f(0)= .1

f(1)= .2

f(2)= .3

f(3)= .2

f(4)= .2.

Expectation of a discrete probability function f of the random variable x is given by ∑ x × f(x).

Thus the expected value of demand is given by

0.1 × 0 + 0.2 × 1 + 0.3 × 2 + 0.2 × 3 + 0.2 × 4 = 2.2.

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3 years ago

Yuri purchased 8 trees to have planted at his house. The store charged a delivery fee of $5 per tree.

cestrela7 [59]

Answer:

$16.

Step-by-step explanation:

Let t represent the cost of each tree.

We have been given that Yuri purchased 8 trees to have planted at his house. So the cost of 8 trees will be 8t.

We are also told that the store charged a delivery fee of $5 per tree. So the delivery charges of 8 trees will be $8\times \$5=\$40$

The total cost of purchasing 8 trees will be $8t+40$ .

Since the total cost of the trees including the delivery was $168, so we can get an equation as:

$8t+40=168$

$8t+40-40=168-40$

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Upon dividing both sides of our given equation by 8, we will get:

$\frac{8t}{8}=\frac{128}{8}$

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Therefore, the cost of each tree is $16.

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3 years ago

Common core question please help!!!

Maru [420]

She has 648 shirts.

Work:
Lisa has 42 pineapples. 4 + 2 = 6
Johnny has 6 marbles.
42 + 4 + 2 + 6 = 54
54 + 5 + 4 = 63
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But 72 is a multiple of 6!
Let's go further:
72 * 6 = 432

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3 years ago

Solve by elimination:

neonofarm [45]

Answer:

x=−8

y=6=

Step-by-step explanation:

3x+4y=0

5x−3y=−58

In order to solve by elimination, coefficients of one of the variables must be the same in both equations so that the variable will cancel out when one equation is subtracted from the other.

3x+4y=0,5x−3y=−58

To make 3x and 5x equal, multiply all terms on each side of the first equation by 5 and all terms on each side of the second by 3.

5×3x+5×4y=0,3×5x+3(−3)y=3(−58)

Simplify.

15x+20y=0,15x−9y=−174

Subtract 15x−9y=−174 from 15x+20y=0 by subtracting like terms on each side of the equal sign.

15x−15x+20y+9y=174

Add 15x to −15x. Terms 15x and −15x cancel out, leaving an equation with only one variable that can be solved.

20y+9y=174

Add 20y to 9y.

29y=174

Divide both sides by 29.

y=6

Substitute 6 for y in 5x−3y=−58. Because the resulting equation contains only one variable, you can solve for x directly.

5x−3×6=−58

Multiply −3 times 6.

5x−18=−58

Add 18 to both sides of the equation.

5x=−40

Divide both sides by 5.

x=−8

The system is now solved.

x=−8,y=6

Coordinates are: (-8,6)

Graph:

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3 years ago