1. 3x+y=52x-y=102. 2x+2y=3X-4y=-1

Mathematics

2 answers:

schepotkina [342]2 years ago

3 0

1. X=5 and Y=-15

2. X=1 and Y=0.5

PtichkaEL [24]2 years ago

3 0

1. Since y in first equation is positive and y in second equation is negative, the easiest was to solve this system is:
3x+y+2x-y=5+10
5x=15
x=3

Now use the x to find y:
3*3+y=5
9+y=5
y=5-9
y=-4

2. You can either multiply the first equation by 2 so that we get the same numbers in front of the y but with different signs or simply express one of the variables and write it in second one.
First way:
2x+2y=3 /*2(multyplying by 2)

4x+4y=6 (that's our first equation)
x-4y=-1 (that's our second equation)

now we just add the equations:
4x+4y+x-4y=6+(-1)
5x=6-1
5x=5
x=1

now we find y:
1-4y=-1
-4y=-1-1
y=-2/-4
y=1/2

Second way:
We express x from the second equation and get:
x=-1+4y
now we change x in the first equation with our new x:
2*(-1+4y)+2y=3
-2+8y+2y=3
10y=5
y=1/2

x=-1+4*(1/2)
x=-1+2
x=1

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Starks sculpture 30 cubed is a cube with sides 30 inches long. Whats its volume

Zolol [24]

Answer: $27000\text{ cubic inches}$

Step-by-step explanation:

Given : Starks sculpture 30 cubed is a cube with sides 30 inches long.

We know that the volume of a cube is given by :-

$\text{Volume}=(side)^3$

Then , the volume of Starks sculpture 30 cubed will be :

$\text{Volume}=(30)^3\text{ cubic inches}$

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2 years ago

Please help not sure if baby has any correct

Elodia [21]

So I think maybe the example for the first problem created some confusion, and you may want to have your child take another look.

If we numbered the top half 1 to 9 going from left to right, numbers 1, 2, 6, 7 and 8 are right. They worked because the top number (numerator) perfectly fit into the bottom number (denominator). This is not true for the rest.

The key is to find the largest number that you can think of that will go into BOTH the top and the bottom evenly.

So for number 3: 18/24; 18 does not fit evenly into 24. The highest number that will fit into both is 6, so you divide both top and bottom by 6 and your answer is 3/4.

Number 4: 45/54; the highest number that goes into both is 9, so you divide both top and bottom by 9 and your answer is 5/6.

Number 5: 55/66; the highest number that can go into both is 11, so the answer is 5/6.

Is this making sense?

The bottom, numbering 1 to 9 from left to right. The correct ones are 1, 6 and 9.

For 2: 14/41 is about 15/40. Both can be divided by 5, so the answer is 3/8.

For 3: 20/81 is about 20/80, and 2/8 is close, but can still be divided by 2, so the answer is 1/4.

For 4: 24/49 is closer to 25/50 than 20/50. 25/50 can be divided by 25, so the answer is 1/2.

For 5: it was all correct, but the answer can be further reduced from 2/8 to 1/4.

For 7: 23/72 is about 25/75, and 25 goes into both, so it reduces to 1/3.

For 8: 13/21 is about 15/20, and 5 goes into both, so the answer is 3/4.

As your child continues to learn this, remember that if he or she gets an answer like 2/6 or 6/12, they should ask themselves if they can further reduce the fractions- 2/6 reduces to 1/3, and 6/12reduces to 1/2. I know it's confusing, but they do get the hang of it with practice

5 0

2 years ago

I need help <br> this is due today at 4

Mrrafil [7]

Answer:

Hi The Answer is A.

Step-by-step explanation:

The Answer is A Because of the funter travel of the X.

x*y=z

Hope This Helps.

My name is John henry.

4 0