A triangle has angles of #7x + 10, x + 20,# and #2x#. What is the measure of the largest angle?

1 Answer
Dec 21, 2015

#115˚#

Explanation:

The sum of the measures of the angles of a triangle is always #180˚#.

Thus,

#(7x+10)+(x+20)+2x=180#

Combine like terms.

#(7x+x+2x)+(10+20)=180#

#10x+30=180#

#10x=150#

#x=15#

Plug #x# in to all the expressions representing the angle measures to find the largest angle.

#7x+10rarr105+10=115˚#

#x+20rarr15+20=35˚#

#2xrarr30˚#

Therefore, the triangle's largest angle is #115˚#.