Question

Find an equation of variation where y varies directly as x and y = 2 when x = 10, find y when x = -25.

Answer 1

y varies directly as x, so

y = kx

for some constant k

They give you y = 2 when x = 10, which means

2 = k*10

From here, solve for k. Let me know what you get.

Answer 2

y=5

Answer 3

no, and it's not y = 5 as it should be k = something

Answer 4

2 = k*10

2/10 = k

1/5 = k

k = 1/5

Answer 5

on my paper it has y= allready there

Answer 6

well finding k is an intermediate step

Answer 7

you don't report the value of k in this case

Answer 8

so because y = kx and k = 1/5, we know that

y = kx

y = (1/5)x

From here, plug in x = -25 and evaluate to find y

Answer 9

anyone help me

Answer 10

what do you get when you plug x = -25 into y = (1/5)x

Answer 11

-5

Answer 12

good you got it

Answer 13

Thanks @jim_thompson5910

Answer 14

you're welcome