If y varies directly as x, and y =-4 when x=8, find y when x=3

Another way of looking at it!

y

=

10

Explanation:

This is a ratio question in disguise.

By parts of the question:

"When y varies directly with x"

→

y

x

"

"if y=8 when x=4"

→

.

.

y

x

=

8

4

"how do you find y when x=5"

→

y

x

=

8

4

=

y

5

so

y

=

8

×

5

4

=

10

This is the same thing as using 'k' in the other solution

Step-by-step explanation:

since the airplane is moving with constant speed then the distance travelled can be calculated by x=u*t

in km/h would be:

x=640*3.5=2.240 km

in m/s would be:

u=640 km/h= 640.000 m/h =640.000/ 3600 m/s =177.8 m/s

t= 3.5 h= 3.5 * 3600 s=12.600 s

then x=u*t= 177.8*12.600= 2.240.280 m

hi,

i'm 75% sure the answer is 1,1 to both lines.

have a great day