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help123456
 3 years ago
a^2 – a – 20 can you help me solve this idk why I keep getting messed up on this
help123456
 3 years ago
a^2 – a – 20 can you help me solve this idk why I keep getting messed up on this

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mathstudent55
 3 years ago
Best ResponseYou've already chosen the best response.0Set up two sets of parentheses: ( )( ) Place a on the left of each parentheses: (a )(a ) Your middle term is a which means 1a, and your last term is 20 Now look for two numbers that multiply to 20 and add to 1 What are they? That's what goes inside the parenteses on the right sides.

Loujoelou
 3 years ago
Best ResponseYou've already chosen the best response.1K so we have to factor a^2a20. We need to find two factors that when multiplied will equal 1 and when added equal 20. If we go through the factors of 20, we find that the two numbers that do this are 5 & 4. 5*4=20 & 5+4=1 so it fits what we're looking for. Now we put this in the two sets of parenthesis we have (a )(a ) and it becomes (a+4)(a5)

help123456
 3 years ago
Best ResponseYou've already chosen the best response.1wait y is one negative and one positive

Loujoelou
 3 years ago
Best ResponseYou've already chosen the best response.1Because we are looking for 2 numbers that multiply to get 20. A positive*positive=positive negative*negative=positive positive*negative=negative. So that means one of the numbers will be negative & the other positive. Also these 2 numbers have to add up to 1. The only two numbers that will meet this are 5 & 4. 5*4=20 and 5+4=1.

mathstudent55
 3 years ago
Best ResponseYou've already chosen the best response.0It's 5 and 4 because 5 x 4 = 20 and 5 + 4 = 1 So now those numbers go in the parentheses. (a  5)(a + 4) And you're done.
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