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3 years ago

Can someone understand this i know its substitution for sure if i dont get wrong

Mathematics

1 answer:

svlad2 [7]3 years ago

7 0

4x - y = 3

y = 2x + 13

Substitute the second equation into the first equation:

4x - y = 3 [since y = 2x + 13, you can substitute (2x + 13) for "y" in the equation]

4x - (2x + 13) = 3 Distribute/multiply - into (2x + 13)

4x - 2x - 13 = 3

2x - 13 = 3 Add 13 on both sides

2x = 16 Divide 2 on both sides

x = 8

Now that you know x = 8, plug it into one of the equations to find y

y = 2x + 13

y = 2(8) + 13

y = 16 + 13

y = 29

x = 8, y = 29 or (8, 29)

[proof]

4x - y = 3

4(8) - 29 = 3

32 - 29 = 3

3 = 3

y = 2x + 13

29 = 2(8) + 13

29 = 16 + 13

29 = 29

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A sweater that regularly sold for $52 is now on sale at 30% off. What is the sale price?

gulaghasi [49]

Answer:

Step-by-step explanation:

What you have to do is set it up like this

what you have to do is

(30*52) ÷ 100=x

1664 ÷ 100= 16.64

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3 years ago

The original sales price of a jacket to the original price is 3:4. The original price is $64 what is the sales price

natka813 [3]

So we need to find a number that has the same ratio to 64 as 3 has to four. We do this by diving 64 into 4:(this is 16): so the two ratios are different by 16. To find the remaining number we multiply 3 by 16: this is 48. So 48 has the same ratio to 64 as 3 has to 4.

And 48 is the answer!

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3 years ago

"The Fountains of Bellagio" is a choreographed water display set to light and music that takes place in front of the Bellagio Ho

Pepsi [2]

Answer:

a) 4/15

b) 4/15

Step-by-step explanation:

maximum wait is 1 min,2 min,3 min,4 min,5 min,6 min,7 min,8 min,9 min,10 min,11 min,12 min,13 min,14 min,15 min =total 15 values

a) less than 4 min means he has to wait for 1 min, 2 min, 3 min, 4 min=total 4 values

Probability of wait for less than 4 minutes=4/15

b) more than 11 minutes wait means he has to wait for either 12 min, 13 min, 14 min, 15 min=4 values

Probability of wait for more than 11 minutes=4/15

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3 years ago

In a sample of 10 cards, 4 are red and 6 are blue. If 2 cards are selected at random from the sample, one at a time without repl

Charra [1.4K]

The exact answer in fraction from is 2/15

The approximate answer in decimal form is 0.1333 (rounded to four decimal places)

The decimal value 0.1333 is equivalent to 13.33%

These are three ways to say the same basic answer.

===============================================

Explanation:

We have 4 red cards and 6 blue cards giving 4+6 = 10 total.

The probability of picking not blue (aka picking red) is 4/10 because there are 4 red out of 10 total.

If we don't replace the card we picked, then we have 3 red left over out of 9 total. The probability of picking red again is 3/9

Multiply those fractions
(4/10)*(3/9) = (4*3)/(10*9) = 12/90

Now reduce
12/90 = (6*2)/(6*15) = 2/15
note how the GCF 6 cancels

Using a calculator,
2/15 = 0.1333 approximately
The '3's after the decimal point go on forever.

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3 years ago

Determine if the equations are intersecting, parallel, or coincident.<br> 4x +y=-4<br> –8x – 2y = 10

sashaice [31]

Answer:

the equations are coincident.

Step-by-step explanation:

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3 years ago