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3 years ago

What is 30% of 70? Show your work. Is this right? 30/100 = 0.3 x 70 = 21%

1 answer:

4 0

$30\% \ of \ 70=30\% \times 70=\frac{30}{100} \times 70=0.3 \times 70=21$
30% of 70 is 21.

Yes, it's right, but the answer is 21, not 21%.

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Multiply (2+3i)(4+6i)

DochEvi [55]

Answer:

-10+24i

hope that helps

7 0

3 years ago

Read 2 more answers

Please help me I am so confused it would mean a lot.

Alisiya [41]

Step-by-step explanation:

1. The midpoint formula says the coordinates of the midpoint are the average of the endpoints.

x = (x₁ + x₂) / 2

y = (y₁ + y₂) / 2

I'll do #2 and #3 as examples.

2. x = (-4 + 10) / 2 = 3

y = (6 + -10) / 2 = -2

So the midpoint is (3, -2).

3. x = (-3 + -6.5) / 2 = -4.75

y = (-8 + -4.5) / 2 = -6.25

So the midpoint is (-4.75, -6.25).

5 0

3 years ago

ALGEBRA

Lyrx [107]

Step-by-step explanation:

1. yes 4+16 = 20

2. yes 32 - 4 = 28

3. yes 4(10) = 40

4. no 24/6 = 4

6 0

3 years ago

Read 2 more answers

Find the standard equation of a sphere that has diameter with the end points given below. (3,-2,4) (7,12,4)

DiKsa [7]

Answer:

The standard equation of the sphere is $(x-5)^{2} + (y-5)^{2} + (z-4)^{2} = 53$

Step-by-step explanation:

From the question, the end point are (3,-2,4) and (7,12,4)

Since we know the end points of the diameter, we can determine the center (midpoint of the two end points) of the sphere.

The midpoint can be calculated thus

Midpoint = $(\frac{x_{1} + x_{2} }{2}, \frac{y_{1} + y_{2} }{2}, \frac{z_{1} + z_{2} }{2})$

Let the first endpoint be represented as $(x_{1}, y_{1}, z_{1})$ and the second endpoint be $(x_{2}, y_{2}, z_{2})$ .

Hence,

Midpoint = $(\frac{x_{1} + x_{2} }{2}, \frac{y_{1} + y_{2} }{2}, \frac{z_{1} + z_{2} }{2})$

Midpoint = $(\frac{3 + 7 }{2}, \frac{-2+12 }{2}, \frac{4 + 4 }{2})$

Midpoint = $(\frac{10 }{2}, \frac{10}{2}, \frac{8 }{2})\\$

Midpoint = $(5, 5, 4)$

This is the center of the sphere.

Now, we will determine the distance (diameter) of the sphere

The distance is given by

$d = \sqrt{(x_{2} - x_{1})^{2} +(y_{2} - y_{1})^{2} + (z_{2}- z_{1})^{2} }$

$d = \sqrt{(7 - 3)^{2} +(12 - -2)^{2} + (4- 4)^{2}$

$d = \sqrt{(4)^{2} +(14)^{2} + (0)^{2}$

$d = \sqrt{16 +196 + 0$

$d =\sqrt{212}$

$d = 2\sqrt{53}$

This is the diameter

To find the radius, r

From $Radius = \frac{Diameter}{2}$

$Radius = \frac{2\sqrt{53} }{2}$

∴ $Radius = \sqrt{53}$

r = $\sqrt{53}$

Now, we can write the standard equation of the sphere since we know the center and the radius

Center of the sphere is $(5, 5, 4)$

Radius of the sphere is $\sqrt{53}$

The equation of a sphere of radius r and center $(h,k,l)$ is given by

$(x-h)^{2} + (y-k)^{2} + (z-l)^{2} = r^{2}$

Hence, the equation of the sphere of radius $\sqrt{53}$ and center $(5, 5, 4)$ is

$(x-5)^{2} + (y-5)^{2} + (z-4)^{2} = \sqrt{(53} )^{2}$

$(x-5)^{2} + (y-5)^{2} + (z-4)^{2} = 53$

This is the standard equation of the sphere

6 0

3 years ago

What is the value of x? <br><br> Enter your answer in the box.<br><br> X =

melamori03 [73]

Answer:

x=54

Step-by-step explanation:

2x + 2 = 3x - 52

subtract 2x from both sides, now u have:

2 = x - 52

add 52 from both sides, now u have

54 = x

7 0

3 years ago