All categories

2 years ago

Simplify the expression (7 + 9i)(8 - 10i)

Mathematics

1 answer:

NeX [460]2 years ago

6 0

The simplified expression of (7 + 9i)(8 - 10i) is 146 + 2i

<h3>How to simplify the expression?</h3>

The expression is given as:

(7 + 9i)(8 - 10i)

Expand the bracket

7 * 8 + 9i * 8 -7 * 10i - 9i * 10i

Evaluate the products

56 + 72i -70i - 90(i²)

Evaluate the difference

56 + 2i - 90(i²)

In complex numbers;

i² = -1

So, we have:

56 + 2i - 90(-1)

Evaluate

56 + 2i + 90

Add the like terms

146 + 2i

Hence, the simplified expression of (7 + 9i)(8 - 10i) is 146 + 2i

You might be interested in

A package of pairs of insulated costs $. What is the unit price of the pairs of

Kobotan [32]

Answer:

$5.89 per pair

$35.34 6 pairs

$35.34/6=$5.89 per pair

4 0

2 years ago

Tiffany put a $550 item on layaway by making a 15% down payment and agreeing to pay $20 a month. How many months sooner would sh

Harrizon [31]

18 months or 4 times faster

5 0

3 years ago

Read 2 more answers

Two sides of a triangle are 4 cm and 7 cm. What can be the length of its third side to make the triangle possible?

Artyom0805 [142]

Answer:

4cm or 7 cm

Step-by-step explanation:

it can make 2 sides equal and make a isosceles triangle

8 0

3 years ago

Mrs. Flores asked her students to write a number, its opposite, and its absolute value, in that order. Four of her students turn

oee [108]

Answer:

Sarah is correct

Step-by-step explanation:

Required

Which of the students is correct

Let a number be x,

Given what the teacher asked the students to do, the solution is:

$Number = x$

$Opposite = -x$

$Absolute = |x|$

Only Sarah got this correctly; others are incorrect.

The proof is as follows.

For Sarah

$Number = 1416$

$Opposite = -1416$

$Absolute =|1416| = 1416$

So, the numbers will be: 1416, -1416 and 1416

<em>Other students are incorrect</em>

4 0

3 years ago

A store is advertising a 40% off sale. Find the new price of a pair of boots that were originally marked $149.00.

Alinara [238K]

Answer:

Step-by-step explanation:

Okay well if 149=100% and there is a 40% we just have to find 60% and to do that we just multiply 149 by 0.60 to get 89.4

149*0.60=89.6

5 0

2 years ago