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Perfect Squares.
Perfect Squares is another way of factoring trinomials (3 terms).
Perfect Square trinomial can be factored using this pattern.
a^2 + 2ab + b^2 = ( a + b)^2
a^2 - 2ab + b^2 = ( a - b)^2
In perfect square , your first and last terms are perfect squares and so the middle term is the product of square roots of the first and last term multiplied by 2.
For example; x^2 + 14x + 49
When you factor the equation above. You know that your answer must be in two brackets.
( ) ( )
Here the since there is no number in front of the variable, it means the variable has a coefficient of 1. So now you would put the factors of 1x^2 in the two brackets.
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Find the square root of the first and last number.
x^2 = x times x
49= 7 times 7
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So now when you find the 2 numbers you put them in the brackets.
( x+7) (x+ 7)
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Simply.
( x+7) ^2
The trinomial that results from squaring a binomial is called a PERFECT SQUARE trinomial.
Example #2 4g^2 + 28g + 49
2g x 7 = 14g x 2 = 28g Which is your middle term.
Solution: (2g + 7) ( 2g +7)
Simply : (2g + 7) ^2
To check your answer simply expand the answer,
(2g +7)^2
= (2g +7) (2g +7)
= 4g^2 +14g +14g + 49
= 4g^2 +28 g +49
So once you get the equation you started with, that means your answer is correct.
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