Question

The measure of the second angle of a triangle is twice the measure of the first angle. The measure of the third angle is 10° less than the measure of the first angle. Find the measure of the second angle.

A. 47.5°
B. 80°
C. 37.5°
D. 95°

Answer 1

A = first angle
B = second angle
C= third angle

C+10=A
2A=B

B/2=A
A-10=C

Answer 2

angless add to 180

they are
x+y+z=180
first angle is x
2nd is y
third is z

2nd angle is 2 times measure of first
y=2x
or
y/2=x

fhird is 10 les than first
z=x-10

sub those

x+y+z=180
(y/2)+y+x-10=180
(y/2)+y+(y/2)-10=180
(y/2)+(y/2)+y-10=180
y+y-10=180
2y-10=180
add 10 to both sides
2y=190
divide both sides by 2
y=95

the second angle is 95 degrees
D is the answer