Step-by-step explanation: Triangles have 180 degrees. To figure out this question you have to find the measure of the last angle. 70+55=125. 180-125=55. So the angles are 70, 55, 55. In an isosceles triangle two sides are equal. Because we know that two angles in the triangle are equal we then know that two sides of the triangle are also equal. Hope this helped :)
Since you said the height of your chair and you desk, chair would go first when subtracting. C= chair c - 29.75 = -10.25 + 29.75 = + 29.75 c= 19.5 So, you chair is 19.5 (19 1/2) inches tall.
