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Someone please help i dont know how to do thisss

Someone please help i dont know how to do thisss-example-1
User Pinhas
by
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1 Answer

3 votes

Answer:

∠A = 52

∠B = 76

∠C = 52

Explanation:

We're given that triangle ABC is isosceles. That means that two of its sides and two of its angles will be the same. Therefore, angle ∠A will be equal to ∠C (we know this because they're formed by a line that goes through the two equal sides, both of which are marked by having lines through them).

Therefore, our three angles are:

∠A = (4x + 4)°

∠B = (5x + 16)°

∠C = (4x + 4)°

Per the properties of a triangle, we can also know that all the internal angles of a triangle should add up to 180°. So we can now set up an expression in which the three angles added together are equal to 180°

(4x + 4) + (5x + 16) + (4x + 4) = 180

Combining like terms --> 13x + 24 = 180

Subtract 24 from both sides --> 13x = 156

Divide both sides by 13 --> x = 12

Now that we've found that x=12, we can just substitute 12 for x to get each angle:

∠A = 4x + 4 = 4(12) + 4 = 52

∠B = 5x + 16 = 5(12) + 16 = 76

∠C = 4x + 4 = 4(12) + 4 = 52

Hope this helps! :)

User Rieckpil
by
5.5k points
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