How can you simplify x^2 +2x-35/x^2 +4x -21 ? Divide the numerator and denominator by (x – 21). Divide the numerator and denominator by (x + 7). Divide the numerator and denominator by (x – 3). Divide the numerator and denominator by (x – 5).

[tex]\dfrac{x^{2}+2x-35}{x^{2}+4x-21}=\dfrac{(x-5)(x+7)}{(x-3)(x+7)}=\dfrac{x-5}{x-3}[/tex]

The second selection is appropriate:
Divide the numerator and denominator by (x + 7).

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isyllus isyllus · Answer 2 · 2019-03-20T18:32:17+01:00

Answer:

"Divide the numerator and denominator by (x + 7)"

B is correct.

Step-by-step explanation:

Given: [tex]\dfrac{x^2+2x-35}{x^2+4x-21}[/tex]

We need to simplify the expression into simplest form.

First we factor each numerator and denominator

[tex]\text{Numerator: }x^2+2x-35[/tex]

[tex]\Rightarrow x^2+7x-5x-35[/tex]

[tex]\Rightarrow (x^2+7x)+(-5x-35)[/tex]

[tex]\Rightarrow x(x+7)-5(x+7)[/tex]

[tex]\Rightarrow (x+7)(x-5)[/tex]

[tex]\text{Denominator: }x^2+4x-21[/tex]

[tex]\Rightarrow x^2+7x-3x-21[/tex]

[tex]\Rightarrow (x^2+7x)+(-3x-21)[/tex]

[tex]\Rightarrow x(x+7)-3(x+7)[/tex]

[tex]\Rightarrow (x+7)(x-3)[/tex]

We can see (x+7) is common at numerator and denominator.

Divide by (x+7) at numerator and denominator..

Hence, "Divide the numerator and denominator by (x + 7)" to get simplest form.