find the area of a triangle

Area of a triangle= 1/2 the base X the height

http://www.mathgoodies.com/lessons/vol1/area_triangle.html

yes, that's right

how do i solve this equation with variables on both sides-the sequel 3(5y=2)-y=2(y-3)

how do you slove

5x+4y=10
2x+y=1
and graph it.its callled a system

I need help on triangles with like figuring out how to find the degre or whatever its called

Area of the triangle : Base x Height over 2