Help me please- thank you

y=-8/5x+4

Step-by-step explanation:

The slope of perpendicular lines is the opposite reciprocal of the original equation.

To get the opposite reciprocal, flip the fraction and use the opposite sign.

Here, the slope is -8/5 because that is the opposite of 5/8.

To get the equation of the line, use point-slope and then distribute to get the equation in y=mx+b format.

Point slope: y-y1=m(x-x1). Use the coordinate (5,-4) in the equation.

y+4=-8/5(x-5)

Multiply (x-5) by -8/5 and simplify.

y+4=-8/5x+8

y=-8/5x+4

r=6

Step-by-step explanation:

Proportions

We know M is directly proportional to

This can be written as

Where k is the constant of proportionality which will be determined knowing that when r = 4, M= 160. Substituting in the equation above:

Solving for k:

The equation is:

Now find r when M=540:

Dividing by 2.5:

Taking cube roots:

r=6