Question

If y varies directly with x and y = -7 when x = -1, find x when y = -84.

Answer 1

@easyaspi314

Answer 2

If x and y vary directly, then its equation is y = kx.

So we know y = -7 when x = -1, so substitute, we get
-7 = k(-1)
k = 7

so since k = 7, our equation is y = 7x

So now lets finish the problem...find x, when y = -84,

so -84 = 7(x)
x = -12.

Answer 3

ok thanks again. I tried to do it on my own. But needed help with this last one.

Answer 4

Keep in mind, that:
1) If x and y vary directly, its equation is y = kx
2) If x and y vary inversely, its equation is xy = k

Answer 5

ok

Answer 6

welcome.