Can somebody pls help and explain it rlly good I’ve been stuck on this for hrs pls help

Create and solve a linear equation that represents the model, where squares and triangles are shown evenly balanced on a balance beam. assume the weight of a square is 1 unit and the weight of a triangle is unknown.

What is the location of point g, which partitions the directed line segment from d to f into a 5: 4 ratio? –1 0 2 3

How long must $542 be invested at a rate of 7% to earn $303.52 in interest? in a easier way