Given:
A number is 400.
To find:
The additive inverse of 400.
Solution:
We know that the sum of a number and its additive inverse is 0.
If "a" is number and "b" is its additive inverse, then

Let x be the additive inverse of 400. Then,

Subtract both sides by 400.


Therefore, the additive inverse of 400 is
.
Answer:
18 and 65
Step-by-step explanation:
under 18 would be 17 and under, therefore not including 18 year olds. obviously they are not 19 yet either, so they wouldn't fall into either category, therefore they may be unsure of what to answer.
same with 65 year olds; they are more than 64 year old, but not yet /over/ 65, therefore they would not fit into either category either.
Answer:
3,225
Step-by-step explanation:
principal times interest time rate
She has 445 left after the bear ate some so
21 × 12 = 252
252 + 445 = 697 acorns
she should maybe bother the bear so he can't hibernate, or steal his food so he knows what it's like
Answer:
Solution : (15, - 11)
Step-by-step explanation:
We want to solve this problem using a matrix, so it would be wise to apply Gaussian elimination. Doing so we can start by writing out the matrix of the coefficients, and the solutions ( - 5 and - 2 ) --- ( 1 )

Now let's begin by canceling the leading coefficient in each row, reaching row echelon form, as we desire --- ( 2 )
Row Echelon Form :

Step # 1 : Swap the first and second matrix rows,

Step # 2 : Cancel leading coefficient in row 2 through
,

Now we can continue canceling the leading coefficient in each row, and finally reach the following matrix.

As you can see our solution is x = 15, y = - 11 or (15, - 11).