Solve pls brainliest

Which formula gives the area of a triangle? a=1/2(b+h)

Is each relation a function? if so, state whether it is one-to-one or many-to-one. 3. (-4,7), (-3,5), (1,4), (3,-8), (5,-11) 4. (-4,8), (-2,4), (0,1), (2,4), (4,8) 5. (-2, 1), (-2,3), (0,-3), (1,4), (3,1)

Which graph represents the solution set for the given system of inequalities? x+2y< 3 x+y> 4 3x-2y> 4