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3 years ago

Hurry 50 points for correct answer

Mathematics

1 answer:

Ad libitum [116K]3 years ago

4 0

Answer: "7 is a solution to the original equation. The value –1 is an extraneous solution."

Step-by-step explanation:

The equation $x=\sqrt{6x+7}$ can be solved by squaring both sides:

$x^2 = 6x + 7\\\\x^2 - 6x - 7 = 0\\\\(x-7)(x+1) = 0$

We can see that -1 and 7 are solutions, but make sure they are not extraneous by substituting them in the original equation:

$1 = \sqrt{-1}\\ 7 = \sqrt{49}$

The square root of 49 equals 7, but the square root of -1 is an imaginary number.

The correct choice is "7 is a solution to the original equation. The value –1 is an extraneous solution."

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I really need help some one please

Alika [10]

The factorization of A is y = (x - 8)(x + 7).
The factorization of B is y = (x + 1)(x - 4)(x - 5)

In order to find these, you must first find where each graph crosses the x-axis. In the first problem it does so at 8 and -7. In order to find the correct parenthesis for those, you need to write it out as a statement and then solve for 0.

x = 8 ---> subtract 8 from both sides
x - 8 = 0
This means we use (x - 8) in our factorization.

You then need to repeat the process until you have all the pieces. In the second problem, there will be 3 instead of 2 since it crosses the axis 3 times.

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3 years ago

A coach for a little league baseball team is ordering trophies for the team. Players on the team are allowed to choose between 2

Natali5045456 [20]

Answer:

y= 5.99(g) + 6.49(u)

Step-by-step explanation:

1) First you determine the variable in the equation $5.99, $6.49, g, and u.

2) Then analyze the equation and identify that each gold baseball trophy (g) is worth $5.99, and each uniform baseball trophy (u) is worth $6.49 each.

3) Since you are finding the total you insert a plus sign.

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3 years ago

The table shows the battery life of four different mobile phones. Mobile Phone Battery Life Phone Battery Life (hours) A 20 B 25

Oliga [24]

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3 years ago

Solving Rational Inequalities and use sign diagram to sketch the graph. Image attached for better understanding.

Studentka2010 [4]

Answer:

x ∈ (-∞, -2) ∪ (2, ∞)

Step-by-step explanation:

To solve this problem we must factor the expression that is shown in the denominator of the inequality.

So, we have:

$x ^ 2-4 = 0\\x ^ 2 = 4$

So the roots are:

$x = 2\\x = -2$

Therefore we can write the expression in the following way:

$x ^ 2-4 = (x-2)(x + 2)$

Now the expression is as follows:

$\frac{(x + 5) ^ 2}{(x-2)(x + 2)}\geq0$

Now we use the study of signs to solve this inequality.

We have 3 roots for the polynomials that compose the expression:

$x = 2\\x = -2\\x = -5$ .

Observe the attached image.

We know that the first two roots are not allowed because they make zero the denominator, we also know that (x + 5) ^ 2 is always positive because it is squared, so it is not necessary to include the numerator in the study of signs.

Note that:

$(x-2)\geq 0$ when $x\geq2$