Answer:
x= 8
Step-by-step explanation:
The equation of direct variation is
y = kx
When y = 50 when x = 40
50 = k* 40
Divide each side by 40
50/40 = k
5/4 = k
The equation is
y = 5/4x
Let y = 10
10 = 5/4x
Multiply each side by 4/5
4/5 * 10 = 5/4 x * 4/5
8 = x