Answer:
y = -20
Step-by-step explanation:
Given that y varies directly with x it means changing x will also cause change in y
Mathematically it can be written as:
y∝x
Removing the proportionality symbol
y = kx
Given y=25 when x=5 Putting the values
[tex]25 = k(5)\\k = \frac{25}{5}\\k = 5[/tex]
Now
[tex]y = 5x[/tex]
We have to find the value of y when x = -4
Putting x=-4
[tex]y = 5(-4)\\y = -20[/tex]
Hence,,
y = -20
