Math Problems?
Factor 64  9y^2
Show how please
11 Answers
 Φ² = Φ+1Lv 77 months ago
64  9y²
= 8²  (3y)²
= 8² + 0  (3y)²
= 8² + (8×3y  8×3y)  (3y)²
= 8² + 24y  24y  (3y)²
= 8(8 + 3y)  3y(8 + 3y)
= (8  3y)(8 + 3y)
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 PhilomelLv 78 months ago
factor 9y^2+64
(9y^264)
(3y8)(3y+8)
(3y+8)(3y+8)
WolframAlpha
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 ComoLv 78 months ago

( 8  3y ) ( 8 + 3y ) = 64 + 24y  24y  9y² = 64  9y²
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 oubaasLv 78 months ago
it is the difference of 2 squares ( 64 = 8^2 ; 9y^2 = (3y)^2 ) ...and you are supposed to know that a^2b^2 = (a+b)*(ab)...therefore :
64  9y^2 = (8+3y)*(83y)
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 az_lenderLv 78 months ago
a^2  b^2 = (a  b)(a + b) =>
64  9y^2 = (8  3y)(8 + 3y)
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 DavidLv 48 months ago
This is a standard factorisation rule that can be useful to remember, the difference of two squares:
a²  b² = (a + b)(a  b).
If you multiply out the bracket, the cross terms cancel.
So if you have something of the form ax²  b for some constants a and b, you know that you can factor them into
ax²  b = (√ax + √b)(√ax  √b)
In this case, both factors are perfect squares, so it works particularly nicely:
64  9y² = (8 + 3y)(8  3y)
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 PuzzlingLv 78 months ago
Learn to recognize the difference of squares and how to factor it:
a²  b² = (a + b)(a  b)
In your case:
a² = 64
b² = 9y²
So:
a = 8
b = 3y
Answer:
(8 + 3y)(8  3y)
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