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MAVERICK [17]
3 years ago
14

Prove that the recurring decimal 0.39 = 13/33

Mathematics
1 answer:
Tcecarenko [31]3 years ago
8 0
x=0.\overline{39}\\100x=39.\overline{39}\\
100x-x=39.\overline{39}-0.\overline{39}\\
99x=39\\
x=\dfrac{39}{99}=\dfrac{13}{33}

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What does the quotiant 35/x represent?
Bumek [7]
When 35 ÷ 7, the quotient would be 5, while 35 would be called the dividend, and 7, the divisor. I hope this helps
5 0
3 years ago
A chicken weighs t lbs. It needs to be cooked for 20 minutes per lb plus an extra 15 minutes. What is the total cooking time? Is
Nostrana [21]

Answer:

Total cooking time = 20t + 15

The expression 15t + 20 is wrong.

Step-by-step explanation:

weight of chicken = t lbs

cook time per lb = 20 minutes

This means that:

1 lb weight requires a cooking time of 20 minutes

1 lb = 20 minutes

∴ t lbs = 20 × t = 20t minutes.

We were also told that each chicken required an extra cooking time of 15 minutes, in addition to the total cooking time due to the weight. Therefore, the total cooking time is calculated thus:

Total cooking time = cooking time due to weight + 15 minutes

Total cooking time = 20t + 15

Hence the expression 15t + 20 is wrong, due to the explanation given above.

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3. Which statements about the line that passes through (-2, 0) and (2, -4) are true?
diamong [38]

Answer:

B, C, and D.

Step-by-step explanation:

Let's go through each answer choice.

A: To find the slope of a line from two points, we use this formula: (y_2-y_1)/(x_2-x_1). Plugging in the values (-2,0) and (2, -4), we get:

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Because option A says the slope is 1, but we got -1, option A is false.

B: To find the y-intercept, we use this formula: b = y_1 - m * x_1

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Since we know the value of b is the y-intercept, we could write the y-intercept as (0,-2). Therefore, option B is true.

C: The equation of a line (in slope-intercept form) is y = mx + b, where y - y-coordinate, m = slope, x = x-coordinate, and b = y-intercept. Since we already solved for the y-intercept and slope, let's plug in those values:

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As you can see, the equation we got here matches the one in option C, meaning it's true.

D: We know that a point is written like this: (x, y). If the x-coordinate is not zero but the y-coordinate is, then it's the x-intercept. Since the question says that (-2,0) is one of the points the line passes through, and option D says that the x-intercept is (-2,0), it's true.

8 0
3 years ago
Read 2 more answers
Write 3x^2-18x-6 in vertex form
Vedmedyk [2.9K]
The standard form of a quadratic equation is \displaystyle{ y=ax^2+bx+c, while the vertex form is:

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What we want is to write \displaystyle{ y=3x^2-18x-6 as y=a(x-h)^2+k

First, we note that all the three terms have a factor of 3, so we factorize it and write:

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Second, we notice that x^2-6x are the terms produced by (x-3)^2=x^2-6x+9, without the 9. So we can write:

x^2-6x=(x-3)^2-9, and substituting in \displaystyle{ y=3(x^2-6x-2) we have:

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Finally, distributing 3 over the two terms in the brackets we have:

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Answer: y=3(x-3)^2-33
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3 years ago
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Svetllana [295]

We can withdraw a equation to give mexico population

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