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2 years ago

8

The sum of 4 times a number and 7 more than the number is 80

1 answer:

marusya05 [52]2 years ago

4 0

Answer:

(4×x) 7> 80 :)

Step-by-step explanation:

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Find the distance between the two points rounding to the nearest tenth (if necessary).

vovangra [49]

Answer: 10.3

Step-by-step explanation:

7 0

2 years ago

4 boys are running a race Pete is ahead of nick by 11 meters Oliver is ahead of Manny by 10 meters Oliver is ahead of Pete by 5

zlopas [31]

Oliver is the runner in 1st place 16 meters ahead of Nick, who is the runner in the last place.

4 0

2 years ago

Read 2 more answers

One of the roots of the equation 3x^2+7x−q=0 is −5. Find the other root and q.

statuscvo [17]

Answer: The answer is $\textup{The other root is }\dfrac{8}{3}~\textup{and}q=40.Step-by-step explanation: The given quadratic equation is[tex]3x^2+7x-q=0\\\\\Rightarrow x^2-\dfrac{7}{3}x-\dfrac{q}{3}=0.$

Also given that -5 is one of the roots, we are to find the other root and the value of 'q'.

Let the other root of the equation be 'p'. So, we have

$p-5=-\dfrac{7}{3}\\\\\\\Rightarrow p=5-\dfrac{7}{3}\\\\\\\Rightarrow p=\dfrac{8}{3},$

and

$p\times(-5)=-\dfrac{q}{3}\\\\\\\Rightarrow \dfrac{8}{3}\times 5=\dfrac{q}{3}\\\\\\\Rightarrow q=40.$

Thus, the other root is $\dfrac{8}{3}$ and the value of 'q' is 40.

3 0

3 years ago

HURRYYYYYYYYY!! What is the equation of the quadratic function with a vertex at (2, 25) and an x-intercept at (7,0)?

tangare [24]

Answer:

$y=-(x-7)(x+3)$

which is none of the choices provided.

Are you sure the question is right or even the choices?

You can even write it as:

$y=-(x+3)(x-7)$ but this is still not a choice.

Step-by-step explanation:

The vertex form of a quadratic is $y=a(x-h)^2+k$ .

This is called vertex form because it gives you the vertex is $(h,k)$ .

We are given that $(h,k)=(2,25)$ which makes our equation:

$y=a(x-2)^2+25$ .

We can find the value of $a$ by plugging in the x-intercept (7,0) for $(x,y)$ into:

$y=a(x-2)^2+25$

$0=a(7-2)^2+25$

$0=a(5)^2+25$

Subtract 25 on both sides:

$-25=a(5)^2$

$-25=a(25)$

Divide both sides by 25:

$\frac{-25}{25}=a$

$-1=a$ .

So the equation for the quadratic is:

$y=-1(x-2)^2+25$

Let's put this into factored form since all the choices are in factored form.

This will require us to multiply the (x-2)(x-2) out:

$y=-1(x-2)(x-2)+25$

$y=-1(x^2-2x-2x+4)+25$

$y=-1(x^2-4x+4)+25$

$y=-x^2+4x-4+25$

$y=-x^2+4x+21$

Factor out -1:

$y=-(x^2-4x-21)$

WE need to find two numbers that multiply to be -21 and add to be -4:

$y=-(x-7)(x+3)$

8 0

3 years ago

Read 2 more answers

For what values of k

sergey [27]

If y = cos(kt), then its first two derivatives are

y' = -k sin(kt)

y'' = -k² cos(kt)

Substituting y and y'' into 49y'' = -16y gives

-49k² cos(kt) = -15 cos(kt)

⇒ 49k² = 15

⇒ k² = 15/49

⇒ k = ±√15/7

Note that both values of k give the same solution y = cos(√15/7 t) since cosine is even.

3 0

2 years ago