Yand x have a proportional relationship, and y = 15 when x = 3. what is the value of x when y = 4? enter your answer in the box. y and x have a proportional relationship, and y = 12 when x = 5. what is the value of y when x = 8? enter your answer in the box

The value of x when y = 4 is 4/5

The value of y when x is 8 is 7.5

If y and x have a proportional relationship and y = 15 when x = 3, hence;

y =  kx

k = k/x

k = 15/3

k = 5

If y = 4, the value of x is calculated as:

x = y/k

x = 4/5

Hence the value of x is 4/5

Similarly, if y and x have a proportional relationship, and y = 12 when x = 5, hence;

y = k/x

k = yx

k = 12 * 5

k = 60

The value of y when x is 8 is expressed as:

y = 60/8

y = 7.5

Hence the value of y when x is 8 is 7.5

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step-by-step explanation:

y = | -2(-2) |     →     y = | 4 |     →     y = 4       ⇒   (-2, 4)

y = | -2(-1) |     →     y = | 2 |     →       y =   2       ⇒   (-1, 2)    

y = | -2(0) |     →     y = | 0 |     →       y = 0         ⇒   (0, 0)

y = | -2(1) |   c →     y = | -2 |     →     y =   2         ⇒   (1, 2)    

y = | -2(2) |     →     y = | - 4 |     →     y =   4         ⇒   (2, 4)