There are two ways to do this but the way I prefer is to make one of the equations in terms of one variable and then 'plug this in' to the second equation. I will demonstrate
Look at equation 1,

this can quite easily be manipulated to show

.
Then because there is a y in the second equation (and both equations are simultaneous) we can 'plug in' our new equation where y is in the second one

which can then be solved for x since there is only one variable

and then with our x solution we can work out our y solution by using the equation we manipulated

.
So the solution to these equations is x=-2 when y=6
If four coordinates are given then:-
- Find length of the sides using distance formula

- Now break down into two triangles .
- Use herons formula and find areas of the triangles .add them and get the area
Answer:true
Step-by-step explanation: