Answer:
B,C,E
Step-by-step explanation:
Multiple each sales total by .1 and then add 150. If they equal then it works, if they don't then it doesn't. No other way I can think of to explain this.
Answer: He is not correct
Step-by-step explanation:
Well to determine whether he is correct find 20% of the basic computer computer and add it to its price to determine if it equals 490 euros
20% * 400 = 80
Now add 80 to 400 to see if it equals 490
400 + 80 = 480
480 ≠ 490
He is wrong
Answer:
The simplify form of the provided expression is: 
Step-by-step explanation:
Consider the provided expression.
Now simplify the above expression as shown below:
as 16/8 = 2
Now again simplify the above expression.
as 2/6 = 1/3
Now, multiply the whole expression with 3.
Hence, the simplify form of the provided expression is:
Solve the following system:
{y = x - 1 | (equation 1)
{2 x - y = 0 | (equation 2)
Express the system in standard form:
{-x + y = -1 | (equation 1)
{2 x - y = 0 | (equation 2)
Swap equation 1 with equation 2:
{2 x - y = 0 | (equation 1)
{-x + y = -1 | (equation 2)
Add 1/2 × (equation 1) to equation 2:
{2 x - y = 0 | (equation 1)
{0 x+y/2 = -1 | (equation 2)
Multiply equation 2 by 2:
{2 x - y = 0 | (equation 1)
{0 x+y = -2 | (equation 2)
Add equation 2 to equation 1:
{2 x+0 y = -2 | (equation 1)
{0 x+y = -2 | (equation 2)
Divide equation 1 by 2:
{x+0 y = -1 | (equation 1)
{0 x+y = -2 | (equation 2)
Collect results:
Answer: {x = -1
{y = -2
9 by 9 to 81 by 1 if it is only whole numbers
