How do you solve the system $x = y + 4$ and $2x - 5y = 2$ by substitution?

Question

4306 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2015-05-21T08:05:50

$x = y + 4$ -----------(1)
$2x - 5y = 2$ -----------(2)

Substituting $x$ from the first equation into the second one gives us:

$2(y+4) - 5y = 2$

$2y+8 - 5y = 2$

$-3y + 8 = 2$

$-3y = 2-8$

$-3y = -6$

Dividing both sides by $-3$ will give us:

$(cancel(-3)y)/cancel(-3) = (-6)/-3$

$color(green)(y = 2$

Substituting $y=2$ in the first equation will give us :

$x = 2 + 4$

$color(green)(x = 6$

The solution to both these equations : $x = 6; y = 2$

Verify :

Substitute the values of $x and y$ in both the equations to see if they are satisfied

How do you solve the system x = y + 4x = y + 4 and 2x - 5y = 22x - 5y = 2 by substitution?