Direct variation has this equation:
y = kx
where k is the constant of variation
y = -5 ; x = -15
y = kx
-5 = k(-15)
-5/-15 = k
1/3 = k
Choice D. y = 1/3 x
Answer:
1) James brother is 10-x years old
2) James was 3 years ago x-3 years old
3) James brother was 3 years ago 7-x years old
4) 3(x-3)=7-x
5) James is 4 years old, his brother is 6 years old
Step-by-step explanation:
3) 10 - x - 3 = 7 - x
5) 3* James age 3 years ago = James brothers age 3 years ago
<=> 3*(x-3) = 7-x
<=> 3x - 9 = 7 - x
<=> 4x = 16
<=> x = 4
Let's make "x" the variable for Maria's age.
And since Maria's father is 20 years older than Maria:
Age of Maria's Father = x + 20.
In 8rows and 3 in each so 8 times 3 is 24