A triangle has sides represented by 9, x, and x + 2. If the

Mathematics

1 answer:

Gennadij [26K]2 years ago

4 0

Answer:

14.

Step-by-step explanation:

1) if the sides of the given triangle are 'a'=9, 'b'=x and 'c'=x+2, then its perimeter can be written as: P=a+b+c or P=9+x+x+2;

2) if according to the condition P=35, then 9+x+x+2=35;

2x=24; ⇒ x=12;

3) if x=12, then a=9; b=12 and 14;

4) finally, c=14 - the required longest side.

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Find a1, for the arithmetic series with S14 = - 420 and d = -6.

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