Question

Help please it’s due

Answer 1

it is C

Explanation:

Answer 2

Explanation:

Since ABC is a triangle,

Angle A + Angle B + Angle C = 180 (Sum of angles in a triangle)

given Angle A = 3x + 1

Angle B = 4x - 17

Angle C = 5x - 20

`3x + 1 + (4x - 17) + (5x - 20) = 180 \\ 3x + 4x + 5x + 1 - 17 - 20 = 180 \\ 12x - 36 = 180 \\ 12x = 180 + 36 \\ 12x = 216 \\ x = 216 / 12 \\ = 18`

Now substitute x into all 3 angles.

A = 3(18) + 1 = 54 + 1 = 55 degrees

B = 4(18) - 17 = 72 - 17 = 55 degrees

C = 5(18) - 20 = 90 - 20 = 70 degrees

Since Angle A = Angle B but not equal to Angle C,

Triangle ABC is a isosceles triangle as 2 angles must be the same for it to be a isosceles triangle.