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3 years ago

Solve the system of equations below

Mathematics

1 answer:

DENIUS [597]3 years ago

4 0

Answer:

The answer is B. (-7,-2)

Step-by-step explanation:

Multiply the first equation by 7,and multiply the second equation by -6.

7(−3x+6y=9)

−6(5x+7y=−49)

Becomes:

−21x+42y=63

−30x−42y=294

Add these equations to eliminate y:

−51x=357

Then solve−51x=357for x:

−51x=357 Divide both sides by -51

x=-7

Write down an original equation:

−3x+6y=9

Substitute−7forxin−3x+6y=9:

(−3)(−7)+6y=9

6y+21=9(Simplify both sides of the equation)

6y+21+−21=9+−21(Add -21 to both sides)

6y=−12

y=-2

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Galina-37 [17]

Answer:

x=4

Step-by-step explanation:

Since x+2 is half the size of 3x:

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3 years ago

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What is Question I (if m<EBF = 117°, fine m<ABE)

Natasha_Volkova [10]

Answer:

m∠ABE = 27°

Step-by-step explanation:

* Lets look to the figure to solve the problem

- AC is a line

- Ray BF intersects the line AC at B

- Ray BF ⊥ line AC

∴ ∠ABF and ∠CBF are right angles

∴ m∠ABF = m∠CBF = 90°

- Rays BE and BD intersect the line AC at B

∵ m∠ABE = m∠DBE ⇒ have same symbol on the figure

∴ BE is the bisector of angle ABD

∵ m∠EBF = 117°

∵ m∠EBF = m∠ABE + m∠ABF

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∴ 117° = m∠ABE + 90°

- Subtract 90 from both sides

∴ m∠ABE = 27°

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4 years ago

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The school cafeteria served three kinds of lunches today to 225 students. The students chose the cheeseburgers three times more

r-ruslan [8.4K]

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3 years ago

Find the slope of the line containing the points (-1,-4) and (-1,4).

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Answer:

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Step-by-step explanation:

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3 years ago

State the linear programming problem in mathematical terms, identifying the objective function and the constraints. A firm makes

Sedbober [7]

Answer:

Maximum profit at (3,0) is $27.

Step-by-step explanation:

Let quantity of products A=x

Quantity of products B=y

Product A takes time on machine L=2 hours

Product A takes time on machine M=2 hours

Product B takes time on machineL= 4 hours

Product B takes time on machine M=3 hours

Machine L can used total time= 8hours

Machine M can used total time= 6hours

Profit on product A= $9

Profit on product B=$7

According to question

Objective function Z= $9x+7y$

Constraints:

$2x+3y\leq 6$

$2x+4y\leq 8$

Where $x\geq 0, y\geq 0$

I equation $2x+3y\leq 6$

I equation in inequality change into equality we get

$2x+3y=6$

Put x=0 then we get

y=2

If we put y=0 then we get

x= 3

Therefore , we get two points A (0,2) and B (3,0) and plot the graph for equation I

Now put x=0 and y=0 in I equation in inequality

Then we get $0\leq 6$

Hence, this equation is true then shaded regoin is below the line .

Similarly , for II equation

First change inequality equation into equality equation

we get $2x+4y=8$

Put x= 0 then we get

y=2

Put y=0 Then we get

x=4

Therefore, we get two points C(0,2)a nd D(4,0) and plot the graph for equation II

Point A and C are same

Put x=0 and y=0 in the in inequality equation II then we get

$0\leq 8$

Hence, this equation is true .Therefore, the shaded region is below the line.

By graph we can see both line intersect at the points A(0,2)

The feasible region is AOBA and bounded.

To find the value of objective function on points

A (0,2), O(0,0) and B(3,0)

Put A(0,2)

Z= $9\times 0+7\times 2=14$

At point O(0,0)

Z=0

At point B(3,0)

Z= $9\times3+7\times0=27$

Hence maximum value of z= 27 at point B(3,0)

Therefore, the maximum profit is $27.

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3 years ago