Question

What's the solution of the system? 2x-y=-7

Answer 1

The answer is (1.5,10)
4x -y = -4
-(2x - y = -7)
-------------------
2x = 3
x = 3/2 or 1.5

Answer 2

Answer:

The answer is (1.5, 10)

Step-by-step explanation:

We can solve this system by apllying substitution in the following way:

(1) 2x-y=-7

(2) 4x-y =-4

1. Simplify one of your variables in terms of the other in any of the two equations

Here its easy to simplify y in equation (1)

2x-y=-7

2x=-7+y

2x+7 = y

y=2x+7 (3)

2. We replace the simplified equation into the other  equation of the system for the simplified variable, in this case y

(3) in (2)

4x-(2x+7) =-4

4x -2x-7 = -4

2x = 7-4

2x = 3

x = 3/2 = 1.5 (4)

3. Repplace the value obtained in the explicit equation of the other variable in this case equation (3)

(4) in (3)

y = 2(1.5)+7 = 3+7 = 10

The system has solution (x,y)=(1.5,10)