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
Read more about complex numbers at:
brainly.com/question/10662770
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Answer:
y = 49
Step-by-step explanation:
The exterior angle of a triangle is equal to the sum of remote interior angles, thus
2y + 7 + 61 - y = 117, that is
y + 68 = 117 ( subtract 68 from both sides )
y = 49
Answer: always
Step-by-step explanation:
Answer:
the larger number is 50
Step-by-step explanation:
Notice there are two unknown numbers. Let's address the smaller one as x and the larger one as y. now we can write two equations from translating the phrases given into algebraic expressions:
"the sum of two numbers is 80" can be written as:
Now the second phrase:
"The ratio of those two numbers is 3/5"
Notice here that in our ratio we need to use our small number (x) in the numerator of the quotient, and the larger number (y) in the denominator to make it in agreement with the small and larger numbers of the ratio , and solve for x:
Replace the value of x we just obtained in the first equation we wrote, so we obtain one equation with only one unknown hat we should be able to solve:
Therefore the larger number (y) equals 50.