Factor x^2 + 4x - 21
2 answers:
Answer:
Step-by-step explanation:
So we want to factor the expression:
When factoring, we want to find two numbers that equals (a)(c) and add up to b. We can then substitute it for b.
So, we want two numbers that when multiplied equals (1)(-21)=-21 and adds up to 4.
We can use 7 and -3.
So:
Factor out an x from the first two terms, and a 7 from the third and fourth terms:
Grouping:
And we are done :)
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The algebra tiles shows the polynomial x² - 2x - 8
<h3>Polynomial</h3>
Polynomial is an expression that involves only the operations of <em>addition, subtraction, multiplication</em> of variables.
Algebra tiles are square and rectangle shaped tiles or tiles that represent numbers and variables.
From the image:
Polynomial = x² + x + x - x - x - x - 1 - 1 - 1 - 1 - 1 - 1 - 1 - 1 = x² - 2x - 8
The algebra tiles shows the polynomial x² - 2x - 8
Find out more on Polynomial at: brainly.com/question/2833285
