The speed of sound in hydrogen is about 3.9 times its speed in air. If its speed in hydrogen is almost 1287 m/s, what is its speed in air?

330 m/s

Step-by-step explanation:

Divide 1287 m/s by 3.9 to get the speed of sound in air as given that the speed of sound in hydrogen is 3.9 times it's speed in hydrogen.

Hope this makes sense.

Good luck!!

hello from mrbilldoesmath!

answer:

x - 3

discussion:

x^2 - 9 = (x-3) (x+3)   so

(x^2-9)/ (x + 3) = x-3

you,

mrb

the system of inequalities is

step-by-step explanation:

step 1

find the equation of the dashed line

we have the points

(0,0) and (3,1)

the line passes through the origin, so, is a direct variation

find the slope

the equation of the dashed line is

the solution of the inequality a s the shaded area above the dashed line

therefore

the equation of the inequality a is

step 2

find the equation of the solid line

we have the points

(4,0) and (0,4)

find the slope

the equation of the solid line is

the solution of the inequality b s the shaded area below the solid line

therefore

the equation of the inequality b is

step 3

the system of inequalities is