triangle upper T upper I upper C is an Isosceles triangle with a vertex angle I. If the measure of angle upper I equals 90 degrees, then find the measure of angle upper T.

(1 point)
Responses

15°
15°

45°
45°

90°
90°

30°

30°

Since triangle TIC is an isosceles triangle, angle TIC and angle C are congruent. If the measure of angle I is 90 degrees, then the sum of angle C and angle TIC must be 90 degrees as well.

Let's label angle TIC as angle T. Since angle TIC and angle C are congruent, angle C will also be labeled as angle T. Therefore, the measure of angle T is 90 degrees.

So the correct answer is 90°.

To find the measure of angle T in an isosceles triangle with a vertex angle I measuring 90 degrees, we need to apply the properties of isosceles triangles.

First, let's understand what an isosceles triangle is. An isosceles triangle is a triangle that has two equal sides (called the legs) and two equal angles opposite those sides.

In our given triangle, we are told that angle I measures 90 degrees. Since we know that the sum of angles in a triangle is 180 degrees, we can deduce the following:

Angle T + Angle T + Angle I = 180 degrees

Since angle I is given as 90 degrees, we can substitute this value into the equation:

Angle T + Angle T + 90 degrees = 180 degrees

Simplifying the equation further, we have:

2 * Angle T + 90 degrees = 180 degrees

Subtracting 90 degrees from both sides of the equation, we get:

2 * Angle T = 90 degrees

Dividing both sides of the equation by 2, we find:

Angle T = 45 degrees

So, the measure of angle T in the given isosceles triangle is 45 degrees.

Therefore, the correct answer is 45°.