Question 341693
The right and left angle equal each other.
The top and bottom angles equal each other.
The sum of all 4 angles equals 360.
{{{4y=x+y+10}}}
1.{{{-x+3y=10}}}
.
.
.
{{{2x+2x+4y+4y=360}}}
{{{4x+8y=360}}}
2.{{{x+2y=90}}}
Add eq. 1 and eq. 2,
{{{-x+3y+x+2y=10+90}}}
{{{5y=100}}}
{{{highlight(y=20)}}}
Then from eq. 1,
{{{-x+60=10}}}
{{{-x=-50}}}
{{{highlight(x=50)}}}