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The perimeter of a triangle is 7a-11b. If two of its sides are 2a+b and a-9b, what is the third side?

User Joanie
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1 Answer

1 vote
you subtract the 2 given sides from the perimeter so its

7a - 11b - (2a + b) - (a - 9b) ( Note the 2 sides must be in parantheses)

= 7a - 11b - 2a - b - a + 9b

adding like terms:-

= 4a - 3b
User Andrew Cowenhoven
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