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Amiraneli [1.4K]

3 years ago

14

Place the following steps in order to complete the square and solve the quadratic equation,x^2+7=0

1 answer:

forsale [732]3 years ago

6 0

X^2+7=0
this can be written as:
x^2+0x+7=0
To solve using completer square we proceed as follows:
x^2+0x=-7
but
c=(b/2a)^2
c=(0/2*1)^2=0
hence
x^2+0x+0=-7+0
this will be simplified as:
x^2=-7
getting the square root of both sides gives us:
sqrt(x^2)=sqrt(-7)
x=+/-√-7
but √-1=i
hence our answer will be:
x=+/-7i

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How do you solve this equation: 80x =

Pepsi [2]

Answer:

Divide by 80 on both sides

7 0

3 years ago

56. How many tangent lines to the curve <img src="https://tex.z-dn.net/?f=y%3Dx%20%2F%28x%2B1%29" id="TexFormula1" title="y=x /(

PIT_PIT [208]

There are 2 tangent lines that pass through the point

$y=\frac{1}{(-1+\sqrt{3)^2} } (x-1)+2$

and

$y=\frac{1}{(-1-\sqrt{3)^2} } (x-1)+2$

Explanation:

Given:

$y=\frac{x}{x+1}$

The point-slope form of the equation of a line tells us that the form of the tangent lines must be:

$y=m(x-1)+2$ $[1]$

For the lines to be tangent to the curve, we must substitute the first derivative of the curve for $m$ :

$\frac{dy}{dx} =\frac{d(x)}{dx}(x+1)-x^\frac{d(x+1)}{dx} \\ \\$

$\frac{dy}{dx} =\frac{x+1-x}{(x+1)^2}$

$\frac{dy}{dx}= \frac{1}{(x+1)^2}$

$m=\frac{1}{(x+1)^2}$ $[2]$

Substitute equation [2] into equation [1]:

$y=\frac{x-1}{(x+1)^2}+2$ $[1.1]$

Because the line must touch the curve, we may substitute $y=\frac{x}{x+1}:$

$\frac{x}{x+1}=\frac{x-1}{(x+1)^2}+2$

Solve for x:

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

$x^2+x=x-1+2x^2+4x+2$

$x^2+4x+1$

$x\frac{-4±\sqrt{4^2-4(1)(1)} }{2(1)}$

$x=-2$ ± $\sqrt{3}$

$x=-2$ ± $\sqrt{3}$ <em> </em> $and$ $x=-2-\sqrt{3}$

There are 2 tangent lines.

$y=\frac{1}{(-1+\sqrt{3)^2} } (x-1)+2$

and

$y=\frac{1}{(-1-\sqrt{3)^2} } (x-1)+2$

8 0

2 years ago

FinnZ [79.3K]

Answer:

Her wage on the 8th day is $105 ⇒ answer d

Step-by-step explanation:

* <em>Lets explain how to solve the problem</em>

- The average of set of data = The sum of data/the number of data

- The sum of data = the average of set of data × the number of data

∵ Cindy worked for 15 consecutive days

∵ She is earning an average wage of $91 per day

∴ Her total earning = 91 × 15 = $1365

∵ Her average earning during the first 7 days is $87 per day

∴ Her total earning in the first 7 days = 87 × 7 = $609

∵ Her average earning during the last 7 days is $93 per day

∴ Her total earning in the last 7 days = 93 × 7 = $651

- Her total earning in the 14 days is the sum of the earning in the

first 7 days and the earning during the last 7 days

∵ Her total earning in the 14 days = 609 + 651 = $1260

∵ Her total earning in the 15 days is $1365

- To find her wage on the 8th day subtract her wage of the 14 days

from her wage of the 15 days

∴ Her wage on the 8th day = 1365 - 1260 = $105

* Her wage on the 8th day is $105

7 0

3 years ago

Write the equation of line in slope-intercept form.

Galina-37 [17]

y=3x-7 that's the answer

7 0

3 years ago

The triangle shaped entrance to the cavern i 1 1/2 feet tall and 4 feet wide whats the area

oee [108]

A=1/2 b*h
So substitute it in 1/2*1/2*4
1/2*1/2= 1/4
1/4*4= 4/4= 1 so the entrance is 1 foot tall

6 0

3 years ago

Read 2 more answers