Which classification best describes the triangle?

The measures of the angles of a triangle can be represented

by the expressions x°, (x + 20)°, and (2x)°.

The measures of the angles of a triangle can be represented

by the expressions x°, (x + 20)°, and (2x)°.

Angles of a triangle add up to 180°

x + x + 20 + 2x = 180 {added angles up and set equal to 180}

4x + 20 = 180 {combined like terms}

4x = 160 {subtracted 20 from both sides}

x = 40 {divided both sides by 4}

x + 20 = 60 {substituted 40, in for x, into x + 20}

2x = 80 {substituted 40, in for x, into 2x}

40°, 60°, and 80° are the angles

The triangle is an

**acute**triangle {none of the angles are greater than/equal to 90°}

*© Algebra House*