Question

Y varies directly with x, and y = 120 ib when x = 50 ib. Find y if x = 40 ib

Answer 1

Y = kx is the direct variation equation.
Use the x and y given to find k. After finding k use it to write a new equation.
120=k*50
Divide by 50 on both sides
120/50=k 12/5=k
y = (12/5)(40) y=96