Question

Solve the following system: y = x + 3 3x + y = 19 (7,4) (-4,7) (4,7) (4,-7)

Answer 1

For this case we have the following system of equations:

$y = x + 3\\3x + y = 19$

We solve by the substitution method:

We substitute the first equation in the second equation:

$3x + x + 3 = 19$

We add similar terms:

$4x + 3 = 19$

We subtract 3 from both sides of the equation:

$4x = 19-3\\4x = 16$

We divide between 4 on both sides of the equation:

$x = \frac {16} {4}\\x = 4$

We look for the value of the variable y:

$y=x+3\\y=4+3\\y=7$

Finally, the solution of the system is:

$(x, y) :( 4,7)$

Answer:

$(x, y) :( 4,7)$