calculating each of the products
noting that i² = (√- 1 )² = - 1
(1 + 2i)(8i) ( distribute by 8i )
= 8i + 16i² = - 16 + 8i ← complex number
(1 + 2i)(2 - 5i) ( expand using FOIL )
= 2 - 5i + 4i - 10i²
= 2 - i + 10 = 12 - i ← complex number
(1 + 2i)(1 - 2i) ( expand using FOIL )
= 1 - 2i + 2i - 4i²
= 1 + 4 = 5 ← real number
(1 + 2i)(4i) ( distribute by 4i )
= 4i +8i² = - 8 + 4i ← complex number
(1 + 2i)(1 - 2i) is the only product which results in a real number
Answer:
d = 22 - x / 25
Step-by-step explanation:
The first thing is to calculate the tank capacity, we know that per gallon 25 miles are traveled and at 500 miles there were still two gallons, therefore:
500 miles / 25 miles / gallon = 20
and how there were still 2
20 + 2 = 22
the tank has a 22 gallon capacity
Therefore the equation would be:
d = 22 - x / 25
where x is the number of miles traveled.
for example, if they have traveled 500 miles it would be:
d = 22 - 500/25 = 22 - 20
d = 2 gallons
we can verify that it is correct because it is what the statement says
10.9 = x% of 34
10.9 is the amount
x% is the percent
34 is the base
Answer:
The slope is 11
Step-by-step explanation:
y=mx+b
Where m is slope, x is variable, and b is the y-intercept.
Answer:
<h3>
9, 11, 13, 15</h3>
Step-by-step explanation:
{k - some integer}
2k+1 - the first odd integer (the least)
5(2k+1) - five times the least
5(2k+1)+3 -<u> three more than five times the least</u>
2k+1+2 = 2k+3 - the odd integer consecutive to 2k+1
2k+3+2 = 2k+5 - the next odd consecutive integer (third)
2k+5+2 = 2k+7 - the last odd consecutive integer (fourth)
2k+1+2k+3+2k+5+2k+7 - <u>the sum of four odd consecutive integers</u>
2k+1 + 2k+3 + 2k+5 + 2k+7 = 5(2k+1) + 3
8k + 16 = 10k + 5 + 3
- 10k -10k
-2k + 16 = 8
-16 - 16
-2k = -8
÷(-2) ÷(-2)
k = 4
2k+1 = 2•4+1 = 9
2k+3 = 2•4+3 = 11
2k+5 = 2•4+5 = 13
2k+7 = 2•4+7 = 15
Check: 9+11+13+15 = 48; 48-3 = 45; 45:5 = 9 = 2k+1
