Asystem of equations is shown.

180x+96y=60
-147x+280y=-273

x=
y=

Since neither the x nor y will cancel just by adding or subtracting the equations you have to multiply the equations to force one variable to cancel.
Since you have a positive and a negative 'x', I would cancel the x's.
Multiply the first equation by 147 and the second equation by 180.
147(180x + 96y = 60) 26460x + 14112y = 8820
180(-147x + 280y = -273) -26460x + 50400y = -49140
Now add the two equations 64512y = -40320
Divide both sides by 64512 y = -5/8
Plug y back into one of the equations and solve for x.
180x + 96(-5/8) = 60
180x - 60 = 60
add 60 to both sides
180 x = 120
divide by 180
x = 2/3
(2/3, -5/8)

A=bxh3.2x1.8=5.76 centimeters square