Answer:
x = 25º, right scalene triangle
Step-by-step explanation:
The interior angles of a triangle add up to 180º.
The red square indicates the angle measure is 90º.
We are left with two other angles, x and (2x + 15).
Let's set up an equation to represent the angle measures
90 + x + (2x + 15) = 180
First, combine like terms.
90 + x + 2x + 15 = 180
105 + 3x = 180
Subtract 105 from both sides to isolate x.
3x = 75
Divide both sides by 3 to further isolate x.
x = 25º
Let's check our answer by plugging it back into our original equation.
90 + x + (2x + 15) = 180
90 + 25 + (2(25) + 15) = 180
Simplify.
90 + 25 + (50 + 15) = 180
90 + 25 + 65 = 180
115 + 65 = 180
180 = 180
Your answer is correct.
x = 25º
Now we need to classify the triangle.
As stated before, the red square indicates the angle measure is 90º. This means our triangle is a right triangle.
Because the other two angle measures are different from one another, we know that the side measures cannot be equal. This leaves us with a scalene triangle.
Your answer is: right scalene triangle
Hope this helps!
