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3 years ago

When you multiply (3+6i)(3+7i) you get an answer of the form a+bi. Find a.

Mathematics

1 answer:

stiks02 [169]3 years ago

5 0

(3 + 6i)(3 + 7i)

FOIL: First, Outside, Inside, and Last

3 x 3 = 9

3 x 7i = 21i

6i x 3 = 18i

6i x 71= 42i

9 + 21I + 18I + 42I = 9 + 81I

a = 9

B = 81I

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Solve the system of linear equations.<br> 3x + 5y = -2<br> 2x - y = 3

natita [175]

Answer:

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Step-by-step explanation:

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3 years ago

What is the average rate of change of f(x) = -x2 + 3x + 6 over the interval –3

Rufina [12.5K]

Answer:

$\frac{\Delta y}{\Delta x} =\frac{f(x_2)-f(x_1)}{x_2-x_1} =\frac{6-(-12)}{3-(-3)} =\frac{18}{6}= 3$

Step-by-step explanation:

To find the average rate of change of a function over a given interval, basically you need to find the slope. The mathematical definition of the slope is very similar to the one we use every day. In mathematics, the slope is the relationship between the vertical and horizontal changes between two points on a surface or a line. In this sense, the slope can be found using the following expression:

$Average\hspace{3}rate\hspace{3}of\hspace{3}change=Slope=\frac{y_2-y_1}{x_2-x_1} =\frac{f(x_2)-f(x_1)}{x_2-x_1}$

So, the average rate of change of:

$f(x)=-x^2+3x+6$

Over the interval $-3$

Is:

$f(x_2)=f(3)=-(3)^2+3(3)+6=-9+9+6=6\\\\f(x_1)=f(-3)=-(-3)^2+3(-3)+6=-9-9+6=-12$

$\frac{\Delta y}{\Delta x} =\frac{f(x_2)-f(x_1)}{x_2-x_1} =\frac{6-(-12)}{3-(-3)} =\frac{18}{6}= 3$

Therefore, the average rate of change of this function over that interval is 3.

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3 years ago

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jenyasd209 [6]

Answer:

the answer is 9,900

Step-by-step explanation:

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3 years ago

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Illusion [34]

Answer:

did u ever get hte answers for this ?

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