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4 years ago

4. The distance between a + 7i and -8 + 4i

Mathematics

1 answer:

Elis [28]4 years ago

4 0

Answer:

Step-by-step explanation:

$\text{The formula of a distance between two complex numbers}\\\\z_1=a+bi,\ z_2=c+di:\\\\d(z_1,\ z_2)=|z_2-z_1|\ \text{where}\ |z|=\sqrt{Re^2+Im^2}\\\\=============================$

$z_1=a+7i,\ z_2=-8+4i\\\\d(z_1,\ z_2)=|(-8+4i)-(a+7i)|=|-8+4i-a-7i|=|-8-a-3i|\\\\=\sqrt{(-8-a)^2+3^2}\\\\d(z_1,\ z_2)=\sqrt{130},\\\\\text{therefore}\ \sqrt{(-8-a)^2+3^2}=\sqrt{130}\Rightarrow(-8-a)^2+3^2=130\\\\\bigg(-(8+a)\bigg)^2+9=130\qquad\text{subtract 9 from both sides}\\\\(8+a)^2=121\iff8+a=\pm\sqrt{121}\\\\8+a=\pm11\qquad\text{subtract 8 from both sides}\\\\a=-19\ or\ a=3$

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Write .125 as a fractionreduced to lowest terms.

horrorfan [7]

The Solution:

We are given the decimal below:

$\begin{gathered} .125 \\ \text{Which also means} \\ 0.125 \end{gathered}$

We are asked to express the given decimal as a fraction in its lowest term.

$0.125=\frac{125}{1000}=\frac{25}{200}=\frac{5}{40}=\frac{1}{8}$

Therefore,

7 0

2 years ago

Write a function g whose graph is a horizontal shrink by a factor of 1/3

mote1985 [20]

Answer:

g(x) = 6|x + 1| - 2

-----------------------------------------

Given:

Function f(x) = 2|x + 3| - 2

Find a function g which is a horizontal shrink by a factor of 1/3 of f(x).

Horizontal shrink by a factor of k is:

g(x) = f(x/k)

Apply this to the given function:

g(x) = f(x : 1/3) = f(3x) = 2|3x + 3| - 2 = 6|x + 1| - 2

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1 year ago

CAN SOMEONE PLEASE PLEASE PLEASE HELP ME, YOU’LL GET FREE EASY POINTS IF YOU GIVE ME THE RIGHT ANSWER !!

bekas [8.4K]

Answer:

reflection across BC
the image of a vertex will coincide with its corresponding vertex
SSS: AB≅GB, AC≅GC, BC≅BC.

Step-by-step explanation:

We want to identify a rigid transformation that maps congruent triangles to one-another, to explain the coincidence of corresponding parts, and to identify the theorems that show congruence.

Triangles GBC and ABC share side BC. Whatever rigid transformation we use will leave segment BC invariant. Translation and rotation do not do that. The only possible transformation that will leave BC invariant is <em>reflection across line BC</em>.

In part 3, we show ∆GBC ≅ ∆ABC. That means vertices A and G are corresponding vertices. When we map the congruent figures onto each other, <em>corresponding parts are coincident</em>. That is, vertex G' (the image of vertex G) will coincide with vertex A.

The markings on the figure show the corresponding parts to be ...

side AB and side GB
side AC and side GC
angle ABC and angle GBC
angle BAC and angle BGC

And the reflexive property of congruence tells us BC corresponds to itself:

side BC and side BC

There are four available congruence theorems applicable to triangles that are not right triangles

SSS -- three pairs of corresponding sides
SAS -- two corresponding sides and the angle between
ASA -- two corresponding angles and the side between
AAS -- two corresponding angles and the side not between

We don't know which of these are in your notes, but we do know that all of them can be used. AAS can be used with two different sides. SAS can be used with two different angles.

SSS

Corresponding sides are listed above. Here, we list them again:

AB and GB; AC and GC; BC and BC

SAS

One use is with AB, BC, and angle ABC corresponding to GB, BC, and angle GBC.

Another use is with BA, AC, and angle BAC corresponding to BG, GC, and angle BGC.

ASA

Angles CAB and CBA, side AB corresponding to angles CGB and CBG, side GB.

AAS

One use is with angles CBA and CAB, side CB corresponding to angles CBG and CGB, side CB.

Another use is with angles CBA and CAB, side CA corresponding to angles CBG and CGB, side CG.

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2 years ago

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Marissa is drawing coins from a bag that contains 5 pennies (yellow), 4 nickels (green), 5 dimes

Anna007 [38]

Answer:

$\frac{4}{16}=\frac{1}{4}=0.25=25\%$

Step-by-step explanation:

Total number of coins in the bag = 5 + 4 + 5 + 2 = 16 coins

Number of nickels in the bag = 4

We have to find the probability that Marissa draws a nickels from the bag.

Probability is defined as the ratio of Number of "Favorable Outcomes" to "Total number of possible outcomes"

In this case total number of possible outcomes is the total number of coins which is 16.

Favorable/Desires outcome is drawing a Nickle from the bag which are 4 in number. So, number of favorable outcomes is 4

Therefore, the probability that she will draw a nickel = $\frac{4}{16}=\frac{1}{4}=0.25=25\%$

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3 years ago

The value of a piece of machinery, in dollars, after t years is described by the function below.

jenyasd209 [6]

Answer:

$6,100

Step-by-step explanation:

12,500-1600(4)

12,500-6,400=6,100

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3 years ago

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