PLEASE HELP FREE 15 POINTS

Please help!! What Find the Error and explain why it is wrong!

Nata [24]

Answer:

First image attached

The error was done in Step E, because student did not multiply $2\cdot x -8$ by the negative sign in numerator. Step E must be $\frac{2\cdot x -5}{(x+4)\cdot (x-4)}$ .

Second image attached

The error was done in Step C, because the student omitted the $2\cdot a \cdot b$ of the algebraic identity $(a+b)^{2} = a^{2}+2\cdot a\cdot b +b^{2}$ . Step C must be $5\cdot x = x^{2}+4\cdot x + 4$

Step-by-step explanation:

First image attached

The error was done in Step E, because student did not multiply $2\cdot x -8$ by the negative sign in numerator. The real numerator in Step E should be:

$3-(2\cdot x -8)= 3-2\cdot x+8 = 11-2\cdot x$

Hence, Step E must be $\frac{2\cdot x -5}{(x+4)\cdot (x-4)}$ .

Second image attached

The error was done in Step C, because the student omitted the $2\cdot a \cdot b$ of the algebraic identity $(a+b)^{2} = a^{2}+2\cdot a\cdot b +b^{2}$ . Step C must be $5\cdot x = x^{2}+4\cdot x + 4$

And further steps are described below:

Step D

$x^{2}-x+4 = 0$

Which according to the Quadratic Formula, represents a polynomial with complex roots. That is: ( $a = 1$ , $b = -1$ , $c = 4$ )

$D = b^{2}-4\cdot a\cdot c$

$D = (-1)-4\cdot (1)\cdot (4)$

$D = -17$ (Conjugated complex roots)

Step E

$(x-0.5-i\,1.936)\cdot (x-0.5+i\,1.936) = 0$

Step F

$x = 0.5+i\,1.936\,\lor\,x = 0.5-i\,1.936$

8 0

3 years ago

Find the midpoint of the line segment whose endpoints are (3, 10) and (7, 8).

Stels [109]

Answer:

Option 2 is correct.

Step-by-step explanation:

Given the coordinates of lines segment (3, 10) and (7, 8). we have to find the mid-point of given line segment.

Mid-point formula states that if $(x_1,y_1)$ and $(x_2,y_2)$ are the coordinates of end points of line segment then the coordinates of mid-point are

$(\frac{x_1+x_2}{2},\frac{y_1+y_2}{2})$

∴ Coordinates of mid-point of line segment joining the points (3, 10) and (7, 8) are

$(\frac{3+7}{2},\frac{10+8}{2})=(\frac{10}{2},\frac{18}{2})=(5,9)$

Hence, option 2 is correct.

6 0

3 years ago

Read 2 more answers

The half-life of caffeine in a healthy adult is 4.8 hours. Jeremiah drinks 18 ounces of caffeinated

statuscvo [17]

We want to see how long will take a healthy adult to reduce the caffeine in his body to a 60%. We will find that the answer is 3.55 hours.

We know that the half-life of caffeine is 4.8 hours, this means that for a given initial quantity of coffee A, after 4.8 hours that quantity reduces to A/2.

So we can define the proportion of coffee that Jeremiah has in his body as:

P(t) = 1*e^{k*t}

Such that:

P(4.8 h) = 0.5 = 1*e^{k*4.8}

Then, if we apply the natural logarithm we get:

Ln(0.5) = Ln(e^{k*4.8})

Ln(0.5) = k*4.8

Ln(0.5)/4.8 = k = -0.144

Then the equation is:

P(t) = 1*e^{-0.144*t}

Now we want to find the time such that the caffeine in his body is the 60% of what he drank that morning, then we must solve:

P(t) = 0.6 = 1*e^{-0.144*t}

Again, we use the natural logarithm:

Ln(0.6) = Ln(e^{-0.144*t})

Ln(0.6) = -0.144*t

Ln(0.6)/-0.144 = t = 3.55

So after 3.55 hours only the 60% of the coffee that he drank that morning will still be in his body.

If you want to learn more, you can read:

brainly.com/question/19599469

7 0

2 years ago

Find the area of each figure.<br> 20 points

hoa [83]

Answer:

purple shape= 1824 inches squared

5 0

2 years ago

Read 2 more answers

Find the missing angle

tatuchka [14]

M 1: 64
M 2: 49
M 3: 87
M 4: 44

5 0

3 years ago