Additive inverses, because their sum is 0
Answer:

Step-by-step explanation:
For #2, remember that
, so
Also, (a+b)(a-b), where a and b are any numbers, (a+b)(a-b)=
. Now, to simplify, or radicalize, a number with surds in the denominator, you have to multiply the denominator by its conjugate. If there is a complex number
, where a and b are any numbers, the conjugate is always
. Lets apply these rules. The conjugate of 4+6i is 4-6i, so do this:

Our answer is (28-3i)/(26)!
Answer:
None of the above.
Step-by-step explanation:
The system of equations which should have the same solution as the system below;
x + 4y = 11
4x + 2y = 16
is
x + 4y = 11
-8x - 4y = - 32
This system of equations is missing from your choices.
The trick is that -2 is multiplied to the second equation of the first system.
i.e -2 (4x + 2y = 16) gives; -8x - 4y = -32
Answer:
36
Step-by-step explanation:
4 x 9 = 36
36 / 4 = 9
Therefore, 36 is 4 times as much as 9.
V (cube)=9³=729 cm³
V (cone)=1/3*π*R²*H= 1/3*π*3²*9=84.8 cm³
V (metal)= 729-84.8=644.2 cm³