How do you find the x and y intercept of $8 x - 3 y = - 21$ $8x − 3y = −21$ ?

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Answer 1 · 2017-03-24T03:33:24

See the entire solution process below:

To find the intercepts by substitution we must do the following:

y-intercept - substitute $0$ $0$ for $x$ $x$ and solve for $y$ $y$ :

$8 x - 3 y = - 21$ $8x - 3y = -21$ becomes:

$(8 \times 0) - 3 y = - 21$ $(8 xx 0) - 3y = -21$

$0 - 3 y = - 21$ $0 - 3y = -21$

$- 3 y = - 21$ $-3y = -21$

$\frac{- 3 y}{- 3} = \frac{- 21}{- 3}$ $(-3y)/color(red)(-3) = (-21)/color(red)(-3)$

$(color(red)(cancel(color(black)(-3)))y)/cancel(color(red)(-3)) = 7$

$y = 7$

The y-intercept is $7$ or $(0, 7)$

x-intercept - substitute $0$ for $y$ and solve for $x$ :

$8x - 3y = -21$ becomes:

$8x - (3 xx 0) = -21$

$8x - 0 = -21$

$8x = -21$

$(8x)/color(red)(8) = (-21)/color(red)(8)$

$(color(red)(cancel(color(black)(8)))x)/cancel(color(red)(8)) = -21/8$

$x = -21/8$

The x-intercept is $-21/8$ or $(-21/8, 0)$

How do you find the x and y intercept of 8x − 3y = −218x−3y=−218x − 3y = −21?