How do you solve $- 8 x - 8 y = 0$ $-8x - 8y = 0$ and $- 8 x + 8 y = - 128$ $-8x + 8y = -128$ ?

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Answer 1 · 2017-09-03T14:10:57

See a solution process below:

Step 1) Solve the first equation for $x$ $x$ :

$- 8 x - 8 y = 0$ $-8x - 8y = 0$

$- 8 x - 8 y + + 8 y = 0 + 8 y$ $-8x - 8y + + color(red)(8y) = 0 + color(red)(8y)$

$- 8 x - 0 = 8 y$ $-8x - 0 = 8y$

$- 8 x = 8 y$ $-8x = 8y$

$\frac{- 8 x}{- 8} = \frac{8 y}{- 8}$ $(-8x)/color(red)(-8) = (8y)/color(red)(-8)$

$1 x = - 1 y$ $1x = -1y$

$x = - y$ $x = -y$

Step 2) Substitute $- y$ $-y$ for $x$ $x$ in the second equation and solve for $y$ $y$ :

$- 8 x + 8 y = - 128$ $-8x + 8y = -128$ becomes:

$(- 8 \cdot - y) + 8 y = - 128$ $(-8 * -y) + 8y = -128$

$8 y + 8 y = - 128$ $8y + 8y = -128$

$16 y = - 128$ $16y = -128$

$\frac{16 y}{16} = - \frac{128}{16}$ $(16y)/color(red)(16) = -128/color(red)(16)$

$y = - 8$ $y = -8$

Step 3) Substitute $- 8$ $-8$ for $y$ $y$ in the solution to the first equation at the end of Step 1 and calculate $x$ $x$ :

$x = - y$ $x = -y$ becomes:

$x = - - 8$ $x = - -8$

$x = 8$ $x = 8$

The Solution Is: $x = 8$ $x = 8$ and $y = - 8$ $y = -8$ or $(8, - 8)$ $(8, -8)$

How do you solve −8x−8y=0-8x - 8y = 0 and −8x+8y=−128-8x + 8y = -128?