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2 years ago

How do you solve linear equations with substitutions?

Mathematics

1 answer:

Nostrana [21]2 years ago

5 0

Answer:

The method of solving "by substitution" works by solving one of the equations (you choose which one) for one of the variables (you choose which one), and then plugging this back into the other equation, "substituting" for the chosen variable and solving for the other. Then you back-solve for the first variable.

Step-by-step explanation:

Solve the following system by substitution.

2x – 3y = –2

4x + y = 24

The idea here is to solve one of the equations for one of the variables, and plug this into the other equation. It does not matter which equation or which variable you pick. There is no right or wrong choice; the answer will be the same, regardless. But — some choices may be better than others.

For instance, in this case, can you see that it would probably be simplest to solve the second equation for "y =", since there is already a y floating around loose in the middle there? I could solve the first equation for either variable, but I'd get fractions, and solving the second equation for x would also give me fractions. It wouldn't be "wrong" to make a different choice, but it would probably be more difficult. Being lazy, I'll solve the second equation for y:

4x + y = 24

y = –4x + 24

Now I'll plug this in ("substitute it") for "y" in the first equation, and solve for x:

2x – 3(–4x + 24) = –2

2x + 12x – 72 = –2

14x = 70

x = 5

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Answer: 7/24

Step-by-step explanation:

Fraction of the items barbecued that are veggie burgers = 3/8

Fraction of the items barbecued that are corn cobs = 1/3

The fraction of the items barbecued that are mushrooms caps will be:

= 1 - (3/8 + 1/3)

The lowest common multiple of 8 and 3 is 24.

= 1 - (3/8 + 1/3)

= 1 - [(3/8 × 24) + [(1/3 × 24)]

= 1 - (9/24 + 8/24)

= 1 - 17/24

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Read 2 more answers

Find the interval in which f(x)=sinx−cosx is increasing or decreasing?

alisha [4.7K]

Answer:

There is no short answer.

Step-by-step explanation:

To find to intervals which f(x) increases or decreases, we first need to find it's derivative.

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I hope this answer helps.

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3 years ago

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butalik [34]

Answer: The complete question is found in the attachment

Step-by-step explanation:

Law of large numbers: The probability of occurrence of an event becomes closer to the theoretical probability as the number of trials increases

P(an ace) = 1/6

= 0.1667

= 16.67%

a) In 600 rolls, the value will be close to 16.67. compared to 60 rolls

Greater than 20% interval doesn't include 16.67%. So, for more than 20% ace, 60 rolls is better.

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3 years ago

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