You can find the length of the sides sing the distance formula:

√((x2-x1)²+(y2-y1)²)

(x2, y2) is a coordinate point

(x1, y1) is a coordinate point

Once you find the two points you are going to use, plug them in into the distance formula and solve for the distance

Then, find the area

If you don't understand this, check this out:

https://web2.0calc.com/questions/halp-plz_12

It's the same question

I hope this helped!