Question

Describe and correct the error in solving the system of linear equations.

5 + 2y = 9
3x - 2y = -1
2x = 10
x = 5

Answer 1

The second equation is incorrect!

Explanation:

Let's break this down line by line:

y=2

x=5

1) 5 + 2y = 9 this equation is basically 5 + (2x2) = 9 meaning that y equals 2. This equation is correct!

2) 3x - 2y = -1 becomes (3x5) - (2x2) = which also basically becomes 15 - 4 which in reality equals 11. This means the equation on the second line is incorrect! Because 3x - 2y = -1 is incorrect and it is actually 3x - 2y = 11

3) 2x = 10 is correct because x=5 meaning that this equation would be 2 x 5 = 10!