In a right-angled triangle, one of the acute angles is 69. What degree does the 2nd acute angle have?

Find the value of the second acute angle of the triangle;

To do this, let’s analyze the condition of the task;

Since the triangle is rectangular, it means from its properties we know that one of the angles of this triangle is 90 °;

And if one of the acute angles of this triangle is 69 °, then we will find the second acute angle from the property of the angles of the triangle;

The sum of all the angles of the triangle is 180 °, so we can write the equation for the angles of the triangle;

Let’s designate the unknown angle as “X” and get the equation;

90 + 69 + X = 180;

X = 21 °.



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