An isosceles triangle has two equal angles, so if one angle is 78°, then the other two angles must be equal to each other. To find the measure of the other two angles, we can subtract 78° from 180° (the total degrees in a triangle) and divide the result by 2.
180° - 78° = 102°
102° / 2 = 51°
Therefore, the other two angles of the isosceles triangle could each measure 51°.
Alternatively, we can use the fact that the sum of the measures of the angles in a triangle is 180°. Let x be the measure of each of the other two angles. Then we have:
78° + x + x = 180°
Simplifying the equation:
78° + 2x = 180°
2x = 180° - 78°
2x = 102°
x = 51°
Therefore, each of the other two angles could measure 51°.
So, the measures that are possible for the other two angles are 51° and 51°.