Please help

<img src="https://tex.z-dn.net/?f=%20-%203%20%2B%205i%20%20%5Cdiv%20%20-%203%20-%204i" id="TexFormula1" title=" - 3 + 5i \div

Likurg_2 [28]

Answer:

$\frac{-11}{25}+\frac{-27}{25}i$ given you are asked to simplify

$\frac{-3+5i}{-3-4i}$

Step-by-step explanation:

You have to multiply the numerator and denominator by the denominator's conjugate.

The conjugate of a+bi is a-bi.

When you multiply conjugates, you just have to multiply first and last.

(a+bi)(a-bi)

a^2-abi+abi-b^2i^2

a^2+0 -b^2(-1)

a^2+-b^2(-1)

a^2+b^2

See no need to use the whole foil method; the middle terms cancel.

So we are multiplying top and bottom of your fraction by (-3+4i):

$\frac{-3+5i}{-3-4i} \cdot \frac{-3+4i}{-3+4i}=\frac{(-3+5i)(-3-4i)}{(-3-4i)(-3+4i)}$

So you will have to use the complete foil method for the numerator. Let's do that:

(-3+5i)(-3+4i)

First: (-3)(-3)=9

Outer:: (-3)(4i)=-12i

Inner: (5i)(-3)=-15i

Last: (5i)(4i)=20i^2=20(-1)=-20

--------------------------------------------Combine like terms:

9-20-12i-15i

Simplify:

-11-27i

Now the bottom (-3-4i)(-3+4i):

F(OI)L (we are skipping OI)

First:-3(-3)=9

Last: -4i(4i)=-16i^2=-16(-1)=16

---------------------------------------------Combine like terms:

9+16=25

So our answer is $\frac{-11-27i}{25}{/tex] unless you want to seprate the fraction too:[tex]\frac{-11}{25}+\frac{-27}{25}i$

6 0

3 years ago

Whats the area of this shape

forsale [732]

First cut the shape into a square, triangle and rectangle. Then add all 3 areas. Area of a quadrilateral is A= b x h So once square is 4 X 4= 16. The rectangle has a area of 4 x 2= 8. The triangle, using the formula 1/2bh has an area of 1/2 x 2 x 4 = 4. So the area of the shape is 16 + 8 + 4 = 28 units

4 0

3 years ago

I am trying to join Brainly for my daughter, she is in the 5th grade and has a hard time. For some reason i am not able to make

stiv31 [10]

Answer:

The only way to make a question is if you have an account unless you want to make another account i think you have to log out and make a new account or go into a different device and make a new account for her.

Step-by-step explanation:

5 0

2 years ago

Find the area of the prism help ASAP!!

stiks02 [169]

To find the surface area of a prism, we must find the area of each side and add them up.

Let's first find the area of the triangular base.

The area of a triangle is $\dfrac{1}{2} bh$
Where b is the base length and h is the height.

The base length of the triangle is 10.5. The height is 10.

$A_B= \dfrac{1}{2}bh= \dfrac{1}{2} \times 10 \times 10.5=52.5$

The triangular base has an area of 52.5 cm².

The triangular top must also have the same area. Thus, it also has an area of 52.5 cm².

Now we to find the length of the 3 rectangles on the side of the prism.

The formula for the area of a rectangle is $A=wl$
where $w$ is the width and $l$ is the length.

All rectangles have a width of 8. They all have different lengths. If we find the area of all the rectangles, we have the following:

$A_1=8 \times 10.5 = 84$

$A_2=8 \times 10 = 80$

$A_3=8 \times 14.5=116$

Now, add up ALL the areas we found. We'll have our surface area once we do this.

$52.5+52.5+84+80+116=385$

The surface area is 385 cm². Hope this helps! :)

5 0

3 years ago

Which of these are NOT expressions? x 1=z x=1 1 x+z

Mkey [24]

Answer:

1, x=1 , 1=z , x

Step-by-step explanation:

6 0

3 years ago

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