The multiplication of the expressions 2i and (4 – 5i) is 10 + 8i. Then the correct option is D.
<h3>What is multiplication?</h3>
It is also known as the product. If the object n is given to m times then we just simply multiply them.
The expressions are 2i and (4 – 5i).
Then the product of the expression will be given as
2i (4 – 5i)
8i – 10i²
And we know that i² = -1
Then we have
8i – 10 (–1)
10 + 8i
More about the multiplication link is given below.
brainly.com/question/19943359
Answer:
B- y=-3
Step-by-step explanation:
Answer: there are eight bicycles and 7 tricycles.
Step-by-step explanation:
Let x represent the number of bicycles that are there.
Let y represent the number of tricycles that are there.
There are a total of 15 bicycles and tricycles. This means that
x + y = 15
A bicycle has 2 wheels and a tricycle has 3 wheels. There are 37 wheels all together if we count them up. This means that
2x + 3y = 37- - - - - - - - - - - - - 1
Substituting x = 15 - y into equation 1, it becomes
2(15 - y) + 3y = 37
30 - 2y + 3y = 37
- 2y + 3y = 37 - 30
y = 7
x = 15 - y = 15 - 7
x = 8
8. You would take 48 (white tiles) then divide it by 6 to get 8. (Grey tiles)
19 trees should be planted to maximize the total
<h3>How many trees should be planted to maximize the total</h3>
From the question, we have the following parameters:
Number of apples, x = 18
Yield, f(x) = 80 per tree
When the number of apple trees is increased (say by x).
We have:
Trees = 18 + x
The yield decreases by four apples per tree.
So, we have
Yield = 80 - 4x
So, the profit function is
P(x) = Apples * Yield
This gives
P(x) = (18 + x) *(80 - 4x)
Expand the bracket
P(x) = 1440 - 72x + 80x - 4x^2
Differentiate the function
P'(x) = 0 - 72 + 80 - 8x
Evaluate the like terms
P'(x) = 8 - 8x
Set P'(x) to 0
8 - 8x = 0
Divide through by 8
1 - x = 0
Solve for x
x = 1
Recall that:
Trees = 18 + x
So, we have
Trees = 18 + 1
Evaluate
Trees = 19
Hence, 19 trees should be planted to maximize the total
Read more about quadratic functions at:
brainly.com/question/12120831
#SPJ1