What is the standard form of $y=(2x+4)(x-5)$ ?

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Answer 1 · 2018-07-24T19:32:55

$y = 2x^2 - 6x - 20$

$y = (2x+4)(x-5)$

Standard quadratic form is $y = ax^2 + bx + c$ .

Use FOIL to simplify:
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Following this image, we can simplify/expand:
Firsts:
$2x * x = 2x^2$

Outers:
$2x * -5 = -10x$

Inners:
$4 * x = 4x$

Lasts:
$4 * -5 = -20$

Combine them all together:
$y = 2x^2 - 10x + 4x - 20$

Combine the like terms $-10x$ and $4x$ :
$y = 2x^2 - 6x - 20$

As you can see, this is in standard quadratic form $y = ax^2 + bx + c$

Hope this helps!

What is the standard form of y=(2x+4)(x-5) y=(2x+4)(x-5) ?