HOW LONG IT TAKES TO SOLVE

A door is held open by two opposing taut cables. The top horizontal cable is known to have a tension of $80$

N $.$ What is the tension in the opposing diagonal cable?

These things apply to the picture at the right:

The door is $2$ m high and $50$ cm wide.

The door knob is $1\mathrm{.}2$ m above the floor.

The outer door edge is $30$ cm from the back wall & $40$ cm from the left wall.

The top horizontal cable is parallel to the back wa

The right anchor point is at the intersection of the floor and the back wal and $80$ cm from the left wall.

Also: g$=10($m$)/($s$^(2))$ and the door mass m$=20$kg$.$

Some perfect squares:

$3^(2)=9,4^(2)=16,5^(2)=25$

$12^(2)=144,13^(2)=169$

Some addition facts:

$9+16=25,25+144=169$