Answer:
-1809 + 899i or
-1809 + √-899
Step-by-step explanation:
foil method
i² = -1
Answer:
The range of the oven is 
Step-by-step explanation:
Consider the provided information.
The internal temperature falls to 20 degrees below the set temperature and turns off when the temperature reaches 5 degrees above the set temperature.
You preheat the oven to 405 degrees before putting a cake in and baking it for an hour at 405.
The internal temperature falls to 20 degrees, therefore the lowest set can be:
405-20=385 degree.
The temperature reaches 5 degrees above the set temperature 405, therefore the upper set is: 405+5=410 degree.
Hence, the temperature will be lying between 385 degree and 410 degree.
This can be written as: 
Hence, the range of the oven is 
Answer:
B
Step-by-step explanation:
The number is between 10 and 49
The number is divisible by 3
Let the 10s digit = x
Let the units digit = y
1/3 * (10x + y) = x + y multiply both sides by 3
10x + y = 3(x +y) remove the brackets.
10x +y = 3x + 3y Subtract 3x from both sides
10x - 3x + y = 3y Combine\
7x + y = 3y Subtract y from both sides.
7x = 3y - y Combine
7x = 2y
x can't be very big. Even taking 1/3 will get out of range is you use 6.
Also x should be an even number. The units digit cannot have a fraction in it.
Try making x = 2
7*2 = 2*y
14 = 2y Divide by 2
14/2 = y
y = 7
So the number is possibly 27. Let's check it out.
- The number is between and includes 10 and 49. 27 is between these two endpoints.
- 27 is divisible by 3
- 1/3(27) = sum of digits
- 9 = (2 + 7)
All of the conditions are met. It's B
Answer: 36 cars and 9 motorcycles
Step-by-step explanation:
- It's given that he has x motorcycles to 4x cars
- After he bought the cars and sold the motorcycles, he had 4x+4 cars to x-4 motorcycles
- Since after this selling/buying, he has 8 times more cars than motorcycles, you can write the equation 4x+4=8(x-4)
- Once you solve you get 36 cars and 9 motorcycles