X + y - z = 9
3x - y + z = -13
____________(+)___
4x = -4 => x = -1 => y - z = 10;
But, x - 2y + 4z = -1 => -2y + 4z = 0 => -y + 2z = 0;
y - z = 10
-y + 2z = 0
_________(+)__
/ z = 10 => y = 20 .
A. There is one solution. The solution is ( - 1, 20, 10 ).
Answer:
a) 
b) -14
c) -3
d) -96
Step-by-step explanation:
a) The parenthesis indicate multiplication.
b) Minus and plus gives subtraction, and the sign you put behind the number is the sign of the largest number you have (in this case it's 21 since we ignore the -)
c) They already have common denominators, all that's left is to do 
d) The parenthesis indicate multiplication.
Good luck!
Every $5 Matthew Has Ava has $2
Answer:
The equation represents an even function
Step-by-step explanation:
For the function above, the value of f(x) is fixed at 3 for positive or negative values of x.
For the absolute value function below, the value of f(x) will always be positive due to the absolute symbol.
In general, a function f(x) is said to be even if;
f(-x) = f(x) such that the function is symmetrical with respect to the y-axis.
Marks of Bobbie = x
Then, marks of Georgia
= 3 times marks of Bobbie
= 3 times m
= 3 × m
= 3m