Question

Suppose y varies directly with x. If y = 6 when x = -2, find x when y = 15.
a. ⅕
b. 5
c. -5
d. -⅕

Answer 1

D because u going to take y6 and y 15 multiples the number it equal to y90 and take x-2 divide into 90

Answer 2

Answer:

C. -5

Step-by-step explanation:

Since, y varies directly with x,

⇒ y ∝ x

⇒ y = kx -----(1)

Where k is the constant of proportionality,

Given,

y = 6 when x = - 2,

From equation (1),

$6=k(-2)$

$\implies k = \frac{6}{-2}=-3$

Again from equation (1),

y = - 3x

If y = 15,

$15 = -3x$

$\implies x = -\frac{15}{3}=-5$

Hence, option C is correct.