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Help if you can, thanks !

Help if you can, thanks !-example-1
User Defmech
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1 Answer

22 votes
22 votes

Answer:

x= 60

Explanation:

We need to find the last inside angle first. Supplementary angles will add up to 180°. 180° - 120° = 60°.

We also know that all of the inside angles of a triangle will add up to 180°.

180° = 60 + (x+5) + (x-5)

Let's get rid of the parentheses to see it easier:

180° = 60 + x + 5 + x - 5

Combine like terms on the right side:

180° = 60 + 2x (the fives canceled each other out)

Subtract 60 from both sides to get the term with x alone:

120° = 2x

Divide both sides by 2 to get x alone:

60° = x

Now check by filling in 60 for x in our equation where all angles add up to 180°.

180° = 60 + (60+5) + (60-5)

180° = 60 + 65 + 55

180° = 60 + 120

180° = 180°

It's right!

User Jason Slobotski
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2.2k points