# If y=kx, where k is a constant, and y=24 when x=6, what is the value of y when x=5?

## Answer choices: A) $- 6 x - 5$ B) $6 x + 5$ C) $6 x - 5$ D) $6 {x}^{2} - 15 x$ I keep getting $y = 20$, but it's none of these choices

Jul 26, 2018

You're right

#### Explanation:

Solving for k,
y = kx
24 = k(6)
k = 4

Substitute in k and given x,
y = 4x = 4(5) = 20

Option A: $- 6 \left(5\right) - 5 = - 35$
Option B: $6 \left(5\right) + 5 = 35$
Option C: $6 \left(5\right) - 5 = 25$
Option D: $6 {\left(5\right)}^{2} - 15 \left(5\right) = 75$

None of the options is equal to 20 when x = 5.