How do you solve the system of equations $3 x + 5 y - 30 = 0$ $3x + 5y - 30 = 0$ and $x - y - 2 = 0$ $x - y - 2 = 0$ ?

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Answer 1 · 2015-09-23T11:50:59

$x = 5$ $x = 5$
$y = 3$ $y=3$

$3 x + 5 y - 30 = 0$ $3x+5y−30=0$ ---------------(1)
$x - y - 2 = 0$ $x−y−2=0$ -------------------(2)

Solve the equation (2) for $y$ $y$

$- y = 2 - x$ $-y = 2-x$
$y = - 2 + x$ $y = -2+x$

Substitute the value of $y = - 2 + x$ $y = -2+x$ in equation (1)
$3 x + 5 (- 2 + x) - 30 = 0$ $3x+5( -2+x)−30=0$

Simplify

$3 x - 10 + 5 x - 30 = 0$ $3x -10+5x −30=0$
$8 x - 40 = 0$ $8x −40=0$
$8 x = 40$ $8x =40$
$x = \frac{40}{8} = 5$ $x=40/8=5$
$x = 5$ $x = 5$

Substitute $x = 5$ $x = 5$ in equation (2)

$5 - y - 2 = 0$ $5−y−2=0$

Simplify -
$3 - y = 0$ $3-y=0$
$- y = - 3$ $-y =-3$
$y = 3$ $y=3$

How do you solve the system of equations 3x+5y−30=03x + 5y - 30 = 0 and x−y−2=0x - y - 2 = 0?