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2 years ago

Solve the system of linear equations by substitution: (SHOW UR WORK) y=-x y=3x-4

Mathematics

1 answer:

LekaFEV [45]2 years ago

4 0

Answer:

x=1

y=-1

Step-by-step explanation:

they have already isolated y in both equations

label both equations

y=-x............1

y=3x-4........2

sub 1 into 2

-x=3x-4

-x-3x=-4

-4x=-4

x=1........ 3

sub 3 into 1

y=-(1)

y=-1

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Please create a word problem using the concept of probability. Please provide the answer to your word problem. *

vitfil [10]

In a game of rock paper scissors, what are the chances that someone playing against a person playing only paper would win?

As for the answer, if you were to make a chart to show rock, paper, and scissors, you'd be able to see that there's a 2/3 chance of winning by choosing rock. With scissors, there's also a 2/3 chance to win. Now with paper, there's only a 1/3 chance to win. Knowing that the other person will only play paper, the best answers would be to choose either rock or scissors.

(there are, of course, flaws with this concept, because the opponent could be lying about playing only paper. More or less, it's a good design to show probability.)

7 0

2 years ago

A fence is to be built to enclose a rectangular area of 450 square feet. The fence along three sides is to be made of material t

Mila [183]

Answer:

The short side is _15___ft and the long side is ___30___ ft.

Step-by-step explanation:

As fence is built in a rectangular area, so we can consider

Let

x be the length of the rectangle

y be width of the rectangle

Given area of rectangle is = 450 ft²

Formula for area of rectangle = Length x width

450 ft² = xy

Solve for y

y = 450/x

now according to given condition

three sides of the fence costs $5 per foot and for the fourth side costs$15 per foot.

We have two condition either the fourth side be x or y

So condition 1: Three sides =(x,y,x) 4-th side = y.

So we can write as 5x,5y,5x and 15 y

Cost C = 5x +5y+5x+15y

= 10x+ 5y+15y

= 5(2x+y) +15y----------------equation 1

= 10x +20y

Adding value of y 450/x

= 10x + 20(450/x)

= 10x + 9000/x

For minimum cost, we can consider the cost to be 0

0 = 10x + 9000/x

Dividing and multiplying by -x/x

0 = -10 +9000/x²

10 = 9000/x²

10x² = 9000/

x²= 900

x = 30

so y = 450/x = 450/30= 15 ft

so adding the values of x and y in equation 1 we will have

cost C= 5(2x+y) +15y----------------equation 1

cost is = 5(2(30)+15) +15(15)

= $600 is the cost

X= 30 y =15

So condition 2: Three sides =(y,x,y) 4-th side = x.

So we can write as 5y,5x,5y and 15 x

Cost C = 5y +5x+5y+15x

= 5x+ 10y+15x

= 5(x+2y) +15x----------------equation 2

= 20x +10y

Adding value of y= 450/x

= 20x + 10(450/x)

= 20x + 4500/x

For minimum cost, we can consider the cost to be 0

0 = 20x + 4500/x

Dividing and multiplying by -x/x

0 = -20 +4500/x²

20 = 4500/x²

20x² = 4500

x²= 4500/20= 225

x = 15

so y = 450/x = 450/15= 30 ft

so adding the values of x and y in equation 2 we will have

cost C= = 5(x+2y) +15x----------------equation 2

cost is = 5(15+2(30) +15(15)

= $600 is the cost

y= 30 x=15

so from both conditions satisfy the cost and the two sides are known as length and width

so dimension will be 15 ft by 30 ft

7 0

2 years ago

Pythagorean theory m3/9=3

Anna71 [15]

Answer:

Step-by-step explanation:

m3/9=3

We move all terms to the left:

m3/9-(3)=0

We multiply all the terms by the denominator

m3-3*9=0

We add all the numbers together, and all the variables

m^3-27=0

#learnwithbrainly

6 0

2 years ago

Eva Maria borrowed money from her father and agreed to pay him 4% simple annual interest. At the end of 7 years, Eva Maria owes

zaharov [31]

4% simple interest after 7 years is 28% interest.

$1736 interest is 28% of $6,200

5 0

3 years ago

Read 2 more answers

Find equation of set of points pieces that its distance from the point 3, 4, -5 and -2, 1, 4 are equal.

Gnesinka [82]

Answer:

Step-by-step explanation:

Suppose we a point $P(x,y,z)$ such that its distance from either the point $A(3,4,-5)$ or $B(-2,1,4)$ is the same.

Using this information we can formula:

distance AP = distance BP

first, let's find the distance from AP, using the distance formula.

$r = \sqrt{(x_1 - x_2)^2 + (y_1 - y_2)^2 + (z_1 - z_2)^2}$

$AP = \sqrt{(3 - x_2)^2 + (4 - y_2)^2 + (-5 - z_2)^2}$

similarly, we can find the distance BP

$BP = \sqrt{(-2 - x_2)^2 + (1 - y_2)^2 + (4 - z_2)^2}$

since both distances are exactly the same we can equate them

$AP = BP$

$\sqrt{(3 - x_2)^2 + (4 - y_2)^2 + (-5 - z_2)^2} = \sqrt{(-2 - x_2)^2 + (1 - y_2)^2 + (4 - z_2)^2}$

we can simplify it a bit squaring both sides, and getting rid of the subscripts.

$(3 - x)^2 + (4 - y)^2 + (-5 - z)^2 = (-2 - x)^2 + (1 - y)^2 + (4 - z)^2$

what we have done here is formulated an equation which consists of any point P that will have the same distance from (3,4,-5) and (-2,1,4).

To put it more concretely,

This is the equation of the the plane from that consists of all points (P) from which the distance from both (3,4,-5) and (-2,1,4) are equal.

3 0

2 years ago