Question

Can an acute isosceles triangle have 2 angles that measure 40 degrees?

Answer 1

`color(blue)("No")`

Explanation:

By definition an acute triangle's angles are all less the `90^@`

Since the sum of all the angles is `180^@`, we have:

`40^@+40^@+theta^@=180^@`

`theta^@=100^@`.

So the third angle is greater than `90^@`. This means the triangle is obtuse, not acute.