If $7x +5 = -2$ , what is the value of $8x$ ?

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Answer 1 · 2017-08-13T13:18:23

See a solution process below:

First, solve the equation for $x$ :

$7x + 5 = -2$

$7x + 5 - color(red)(5) = -2 - color(red)(5)$

$7x + 0 = -7$

$7x = -7$

$(7x)/color(red)(7) = -7/color(red)(7)$

$(color(red)(cancel(color(black)(7)))x)/cancel(color(red)(7)) = -1$

$x = -1$

Now, substitute $color(red)(-1)$ for $color(red)(x)$ in the expression and calculate the value of $8x$

$8color(red)(x)$ becomes:

$8 * color(red)(-1) => -8$

If 7x +5 = -27x +5 = -2, what is the value of 8x8x?