Answer:
y = 40
Explanation:
y=kx
substitute first values from the statement ( if y = 20 then x = -4)
20=k * -4 (" * " means multiply)
bring "-4" to the other side which means you divide 20 by -4
20/-4 = k
k = -5
so now substitute -5 instead of k in the equation
y= - 5x
when x = -8
y= -5 * -8
y= 40
hope this helps :)