Question

One angle of an isosceles triangle measures 90°. Which other angles could be in that isosceles triangle?

Answer 1

Hello from MrBillDoesMath!

Answer:

45 (all three: 45, 45, 90)

Discussion:

Let "x" be the base angle in the isosceles triangle. As base angles are equal in an isosceles triangle and a triangle contains 180 degrees:

x + x + 90 = 180 =>

2x + 90 = 180 => subtract 90 from both sides

2x = 180 -90 =>

2x = 90 => divide both sides by 2

x = 45

Thank you,

MrB

Answer 2

45, 45

Explanation:

We know the three angles of a triangle add to 180

We have one angle is 90, let the other angles be x (They must be the same since it is isosceles)

x+x+90 = 180

2x+90 =180

Subtract 90 from each side

2x+90-90=180-90

2x = 90

Divide by 2

2x/2 = 90/2

x = 45

The other 2 angles are 45 degrees each