So your expression is 49+14√5 +5, combine like terms, and you have
54+14√5 or 49+14√5-5 which equals 44+14√5. The square root of 5 is positive or negative 2.25, so when you multiply √5*√5, you're either multiplying two positives or two negatives, which will give you a positive 5, or you're multiplying a positive and a negative, which will give you a negative 5.
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Verified answer
You just FOIL it:
(7 + √5)(7 + √5)
First: 7*7=......49
Outer: 7*√5=....7√5
Inner: √5*7=......7√5
...combine inner and outer terms: 14√5
Last: √5*√5=5 or -5
So your expression is 49+14√5 +5, combine like terms, and you have
54+14√5 or 49+14√5-5 which equals 44+14√5. The square root of 5 is positive or negative 2.25, so when you multiply √5*√5, you're either multiplying two positives or two negatives, which will give you a positive 5, or you're multiplying a positive and a negative, which will give you a negative 5.
wpf.
(a+b)² = a² + 2ab + b², so
(7 + â5)² = 7² + 2•7•â5 + (â5)² = 49 + 14â5 + 5
(7 + â5)² = 54 + 14â5
(a+b)² = a² + 2ab + b², so
(7 + â5)² = 7² + 2•7•â5 + (â5)² = 49 + 14â5 + 5
(7 + â5)² = 54 + 14â5
(7 + â5)²
= (7)² + 2(7)(â5) + (â5)²
= 49 + 14â5 + 5
= 54 + 14â5
(7 + â5)(7 + â5)
FOIL
49 + 7â5 + 7â5 + (â5)²
49 + 5 + 14â5
54 + 14â5
You would be better to think of it as square two separate variables.
You end up getting 49 + 5, which of course equals 54.