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3 years ago

Please help! Algebra 2!!

Mathematics

2 answers:

Tamiku [17]3 years ago

7 0

Mistake found

3x-2(2x-4)=2

3x - 4x - 8 = 2 instead of 3x - 4x + 8 = 2

Correct answer

x= -13 y= -30

AlladinOne [14]3 years ago

6 0

Answer:

See below.

Step-by-step explanation:

So we have the system of equations:

$3x-2y=21 \text{ and } y=2x-4$

The student took the following steps:

$3x-2(2x-4)=21\\3x-4x-8=21\\-x-8=21\\-x=29\\x=-29\\y=2(-29)-4=-58-4=-62$

The student's mistake is in step 2. He/she distributed incorrectly. You are supposed to distribute the -2 to both terms, so it should be -4x plus 8, since -2 times -4 is positive 8. Fixing that mistake, we will have:

$3x-2(2x-4)=21\\3x-4x+8=21 \\-x+8=21\\-x=13\\x=-13\\y=2(-13)-4=-26-4=-30$

Thus, the final answers should be (-13, -30).

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What's the equation of the parabola that has its vertex at (4,–1) and a y-intercept at (0,7)?

xz_007 [3.2K]

Answer:

because it is given that the vertex is (4, - 1) an an equation C it is clearly seen that the vertex is same.

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3 years ago

What is the solution to -55+q=7 A. a=-62 B. q=62 C. q=42 D. q=-42

Scorpion4ik [409]

Answer:

C, as q = 62.

Step-by-step explanation:

When you have an equation, your goal is to get the letter you are solving for alone. To do this, you employ a simple rule: what you do to one side of the equals sign, you must do the other.

To isolate q in -55 + q = 7, you must add 55 to the left side. q is now alone. However, because we added 55 to the left side, we must also do it to the right! 7 + 55 = 62, so the new right side is 62. Hence, we get to this:

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The answer is now in plain sight!

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2 years ago

Read 2 more answers

Please help! 4^x*5^y=20, 4^y*5^x=20^2, x+y=?

photoshop1234 [79]

Answer:

x + y are either 2 or 4

Step-by-step explanation:

conclusion x + y = 2 OR 4

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2 years ago

2 taps A and B can fill a swimming pool in 3 hours. If turned on alone, it takes tap A 5 hours less than tap B to fill the same

vazorg [7]

Answer:

Tap A will take 2 hours and tap B will take 6 hours to fill the tank when turned on alone.

Step-by-step explanation:

Let tap B fills the pool alone in the time = x hours

So in one hour part of pool will be filled = $\frac{1}{x}$

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So in one hour part of the same pool filled = $\frac{1}{x-5}$

Now both the taps A and B are turned on then time taken to fill the pool = 3 hours.

Part of the pool filled in one hour by both the taps = $\frac{1}{3}$

Now we form an equation

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3(x - 4) = x(x - 5)

x² -5x = 3x - 12

x² - 8x + 12 = 0

x² - 6x - 2x + 12 = 0

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4 0

3 years ago

Find two numbers a and b such that a+b=0 and ab=36

PolarNik [594]

Answer:

b = 6i then a = -6i

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Step-by-step explanation:

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Take the square root of each side

sqrt(b^2) = sqrt(-36)

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a = - (± 6i)

so b = 6i then a = -6i

b = -6i then a = 6i

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3 years ago