How do you evaluate $x^{2} + 2 x$ $x^2+2x$ for the value of x satisfying $5 (x - 3) + 13 = 4 x - 3 (2 - x)$ $5(x-3)+13=4x-3(2-x)$ ?

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Answer 1 · 2017-08-27T12:09:57

If $x = 2$ $x=2$

Then $x^{2} + 2 x = 8$ $x^2 +2x = 8$

There are two stages in this question.

Firstly solve the given equation to find a value for $x$ $x$ which is the solution.

Then substitute that value into the expression to find its value.

$5 (x - 3) + 13 = 4 x - 3 (2 - x)$ $5(x-3)+13=4x-3(2-x)$

$5 x - 15 + 13 = 4 x - 6 + 3 x \leftarrow$ $5x-15 +13 = 4x -6+3x" "larr$ simplify each side

$5 x - 2 = 7 x - 6$ $5x -2 = 7x -6$

$- 2 + 6 = 7 x - 5 x$ $-2+6 = 7x-5x$

$4 = 2 x$ $4 =2x$

$x = 2$ $color(blue)(x=2)$

$x^{2} + 2 x$ $x^2 +2x" "$ becomes:

$2^{2} + 2 (2)$ $color(blue)(2)^2 +2(color(blue)(2))$

$= 4 + 4$ $=4+4$

$= 8$ $=8$

How do you evaluate x2+2xx^2+2x for the value of x satisfying 5(x−3)+13=4x−3(2−x)5(x-3)+13=4x-3(2-x)?