Question

Here is a triangle.

4x + 20
x +32
4x + 20
Does the triangle contain an obtuse angle?.
Explain your reasoning.


Please help me urgent need

Answer 1

No

Explanation:

All angles of a triangle add up to 180°.

4x + 20 + 4x + 20 + x + 32 = 180

1. Simplify

9x + 72 = 180

2. Subtract 72 from both sides.

9x = 108

3. Divide both sides by 9.

x = 12

Replace x by 12 in each angle.

- 12 + 32 = 44°

- 4(12) + 20 = 68°

- 4(12) + 20 = 68°

All of the angles are less than 90°, so they aren't obtuse.

Answer 2

No

Explanation:

the sum of the 3 angles in a triangle = 180°

sum the 3 angles and equate to 180

x + 32 + 4x + 20 + 4x + 20 = 180

9x + 72 = 180 ( subtract 72 from both sides )

9x = 108 ( divide both sides by 9 )

x = 12

then the 3 angles are

x + 32 = 12 + 32 = 44°

4x + 20 = 4(12) + 20 = 48 + 20 = 68°

4x + 20 = 68°

an obtuse angle is greater than 90°

none of the 3 angles in the triangle are obtuse