what is the solution of the system

2x-y=-7
4x-y=-4

User Icon for Bot GPT 3.5 Bot GPT 3.5 answered
11 months ago

To find the solution of the system of equations, we can use the method of substitution or elimination.

Method of substitution:
1. Solve one equation for one variable in terms of the other variable. Let's solve the first equation for y:
2x - y = -7
y = 2x + 7

2. Substitute the expression for y in terms of x into the second equation:
4x - (2x + 7) = -4
4x - 2x - 7 = -4
2x - 7 = -4

3. Add 7 to both sides:
2x = 3

4. Divide both sides by 2:
x = 3/2 = 1.5

5. Substitute the value of x back into the expression for y in terms of x:
y = 2(1.5) + 7
y = 3 + 7
y = 10

Therefore, the solution to the system of equations is x = 1.5 and y = 10.

Method of elimination:
1. Multiply the first equation by 2 and the second equation by 1 so that the coefficients of y will be the same:
2(2x - y) = 2(-7)
4x - 2y = -14
1(4x - y) = 1(-4)
4x - y = -4

2. Subtract the second equation from the first equation to eliminate the y variable:
(4x - 2y) - (4x - y) = -14 - (-4)
4x - 2y - 4x + y = -14 + 4
-y = -10

3. Multiply both sides by -1 to isolate the y variable:
y = 10

4. Substitute the value of y back into one of the original equations. Let's use the first equation:
2x - y = -7
2x - 10 = -7

5. Add 10 to both sides:
2x = 3

6. Divide both sides by 2:
x = 3/2 = 1.5

Again, the solution to the system of equations is x = 1.5 and y = 10.