Answer:
(a) The system of the equations
has no solution.
(b) The system of the equations
has many solutions 
Step-by-step explanation:
(a) To find the solutions of the following system of equations
you must:
Multiply
by 2:

Subtract the equations

0 = -3 is false, therefore the system of the equations has no solution.
(b) To find the solutions of the system
you must:
Isolate x for 

Substitute
into the second equation

The system has many solutions.
Isolate y for 

Answer:
he means 5 2/3
Step-by-step explanation:
Answer:
-1.5m + 4n is the equivalent expression
Step-by-step explanation:
To find the equivalent expression, we combine the like terms.
We are given the following expression:
m + 4n - 2.5m
Combining the like terms:
m - 2.5m + 4n
-1.5m + 4n is the equivalent expression
Solve for x:
x^2 + 4 x + 25 = 0 I ssume that's the notation.
Subtract 25 from both sides:
x^2 + 4 x = -25
Add 4 to both sides:
x^2 + 4 x + 4 = -21
Write the left hand side as a square:
(x + 2)^2 = -21
Take the square root of both sides:
x + 2 = i sqrt(21) or x + 2 = -i sqrt(21)
Subtract 2 from both sides:
x = i sqrt(21) - 2 or x + 2 = -i sqrt(21)
Subtract 2 from both sides:
Answer: x = i sqrt(21) - 2 or x = -i sqrt(21) - 2