1-2 Cos²25°÷(1-2sin²25)

The square of a positive number is equal to its triple added to 28. What is this number?

sashaice [31]

hi brainly user! ૮₍ ˃ ⤙ ˂ ₎ა

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$\huge{ \rm{Answer:}}$

The roots of the equation are 7 and -4, because 7 - 4 = 3 and 7. - 4 = -28

Step-by-step explanation:

The positive number is equal to 7.

Assuming that the number is equal to "x" we have:

$\begin{gathered}x^2 = 3x + 28\\\\x^2 - 3x - 28 = 0\\\\a = 1\\\\b = -3\\\\c = -28\\\end{gathered}$

By the sum and product method, we have:

$\begin{gathered}S = -b / a\\\\S = -(-3) / 1\\\\S = 3\\\\\end{gathered}$

$\begin{gathered}P= c / a\\\\P = 28 / 1\\\\P = 28\\\\\end{gathered}$

4 0

2 years ago

1. Fill in the blanks for the rules for working with exponents:

natima [27]

1.a)add
B) substract
C) multiply
D) one

2) 1002=1.002×10^3

3)2.8×10^-3 < 2.5×10^-2 < 1.2×103 <4×103

5 0

3 years ago

Read 2 more answers

50 points! I understand A. and B. but I would really appreciate help with C.

FromTheMoon [43]

Answer:

$51.72\text{ cells per hour}$

Step-by-step explanation:

So, the function, P(t), represents the number of cells after t hours.

This means that the derivative, P'(t), represents the instantaneous rate of change (in cells per hour) at a certain point t.

C)

So, we are given that the quadratic curve of the trend is the function:

$P(t)=6.10t^2-9.28t+16.43$

To find the instanteous rate of growth at t=5 hours, we must first differentiate the function. So, differentiate with respect to t:

$\frac{d}{dt}[P(t)]=\frac{d}{dt}[6.10t^2-9.28t+16.43]$

Expand:

$P'(t)=\frac{d}{dt}[6.10t^2]+\frac{d}{dt}[-9.28t]+\frac{d}{dt}[16.43]$

Move the constant to the front using the constant multiple rule. The derivative of a constant is 0. So:

$P'(t)=6.10\frac{d}{dt}[t^2]-9.28\frac{d}{dt}[t]$

Differentiate. Use the power rule:

$P'(t)=6.10(2t)-9.28(1)$

Simplify:

$P'(t)=12.20t-9.28$

So, to find the instantaneous rate of growth at t=5, substitute 5 into our differentiated function:

$P'(5)=12.20(5)-9.28$

Multiply:

$P'(5)=61-9.28$

Subtract:

$P'(5)=51.72$

This tells us that at exactly t=5, the rate of growth is 51.72 cells per hour.

And we're done!

7 0

3 years ago

The graph below is a portion of a complete graph. Which graph below is the complete graph assuming it is an even function?

Ierofanga [76]

Answer:

Option b

Step-by-step explanation:

A function is even if and only if f(-x) = f(x).

This means that there is the same value of y for $x_0$ and for $-x_0$

Where $x_0$ is any point belonging to the function .

Therefore you must select a graph whose ordered pairs are of the form $(x_0, y_0)$ and $(-x_0, y_0)$

Therefore the correct answer is option b. Assume that each box in the graph equals 1 unit. Then, for x = 2 y = -3 and for x = -2 y = -3. Then it is shown that the function is even.

8 0

3 years ago

How many unique triangles can be drawn with given side lengths of 8 inches, 10.3 inches, and 13 inches?

REY [17]

Answer: 1

Step-by-step explanation: There can only be one triangle like that!

4 0

2 years ago

Read 2 more answers

1-2 Cos²25°÷(1-2sin²25)​

1-2 Cos²25°÷(1-2sin²25)