Answer:
(4+7i)-2i(2+3i) = 10+3i
Step-by-step explanation:
We need to find the expression that is equivalent to the complex number 10+3i.
Option 1. 2i(4-5i)+(1-7i)
=8i-10i²+1-7i
∵ i² = -1
=8i-10(-1)+1-7i
=8i+10+1-7i
=11+i (incorrect)
Option 2. (4+7i)-2i(2+3i)
=4+7i-4i-6i²
=4+7i-4i-6(-1)
=4+7i-4i+6
=10+3i (Correct)
Option 3. (-3+5i)-3i(4+5i)
= (-3+5i)-12i-15i²
= -3+5i-12i-15(-1)
= -3+5i-12i+15
=12-7i (incorrect)
Option 4. 3i(4+7i)+(11+2i)
= 12i+21i²+11+2i
=12i+21(-1)+11+2i
= 12i-21+11+2i
=14i-10 (incorrect)
Hence, the correct option is (B).
Answer:
x is 35
Step-by-step explanation:
First do 180 -40 and get 140. Then add 3x plus x to get 4x because they are the same value/ Do 140/ 4x and get 35. X equals 35.
Answer:

Step-by-step explanation:
The central angle of the sector representing rent expenses in the pie chart is found by simple rule of three:


Answer:
The answer is 24.
Step-by-step explanation:
Answer:
720 possible ways
Step-by-step explanation:
The gold is awarded to the first position, the silver is awarded to the second position while the bronze is awarded to the third position.
The first position can be taken by any of the 10 runners
Now, the second position can be taken by remaining 9 runners
while the third position can be taken by the renaming 8 runners.
Thus, the number of ways in which these medals can be awarded = 10 * 9 * 8 = 720 ways