Answer:
Some of the other answers are good examples of solving a system of three equations in three unknowns, which is what this problem is asking. Though the simplest way to solve this problem is actually to notice that, if we sum the three equations, we get:
X + Y = 10
X + Z = 20
+ Y + Z = 24
----------------
2X + 2Y + 2Z = 54
Factoring out the 2, we have 2(X + Y + Z) = 54, and dividing both sides by 2 reveals that X + Y + Z = 27.
Step-by-step explanation:
hopefully this helps
Answer:
24 is correct answer
Step-by-step explanation:

hope it helped you:)
The first one is 0,5 the second one is 1,3 last one is 2,1
Answer:
11
Step-by-step explanation:
This is a difference of squares and therefore can be written as (76-1)(76+1)=(75)(77).
So lets look at the factors....
75=3(25)=3(5)(5)
77=7(11)
The biggest prime factor is therefore 11.
Identities used:
Difference of squares a^2-b^2=(a-b)(a+b)
Answer:
52 years old
Step-by-step explanation:
let this mans age be a
400-3a=244
400=244+3a
400-244=3a
156=3a
a=52