Answer:
65
Step-by-step explanation:
(4-7i)(4+7i) =16 + 28i-28i -49i^2 ➡16 - 49i^2
16 + 49 = 65
the fault here is i^2= -1 and -1 multiplied by -49 is +49 not -49
Hello there.
<span>Fifty- three students from 32 different schools signed up for a multi-classroom project. About how many students signed up for the project?
</span><span>B. about 1,800 students
</span>
Given:
In a two-digit number, the tens digit is 5 less than the units digit.
The number itself is five more than three times the sum of its digits.
To find:
The number.
Solution:
Let the two digit number is ab. So,
Tens digit is 5 less than the units digit.
...(i)
The number itself is five more than three times the sum of its digits.
...(ii)
Using (i) and (ii), we get
Putting b=8 in (i), we get
Therefore, the required number is 38.
Answer:
27
Step-by-step explanation:
So first we need to plug in 5 as the variable a and -7 as the variable b
4(5)-(-7)
Next we multiply the 4 and the 5 together to get 20
4(5) = 20 or 4 x 5 = 20
20-(-7)
Now we subtract negative 7 from 20
20-(-7) = 27
This can also be written as 20 plus 7 as a mathematical rule states: two negatives make a positive. So:
20-(-7) = 20 + 7
Both of these are equivalent in every sense of the word and give us our final answer of 27
