If y varies directly as x, and y is 180 when x is n and y is n when x is 5, what is the value of n?
18

30

Step-by-step explanation:

y varies directly with x, so:

y = kx

When x = n, y = 180.

180 = kn

When x = 5, y = n.

n = 5k

Solve for k in the first equation:

k = 180 / n

Substitute into the second equation:

n = 5 (180 / n)

n = 900 / n

n² = 900

n = 30

fahrenheit

step-by-step explanation:

fahrenheit is more precise than celsius. the ambient temperature on most of the inhabited world ranges from -20 degrees fahrenheit to 110 degrees fahrenheit—a 130-degree range. on the celsius scale, that range is from -28.8 degrees to 43.3 degrees—a 72.1-degree range. this means that you can get a more exact measurement of the air temperature using fahrenheit because it uses almost twice the scale.

c. y = 1/4 x + 5

step-by-step explanation:

first, put the equation of the line on the graph into slope-intercept form

(y = mx + b):   y = -4x + 8

second, a perpendicular line has to have "an opposite/reciprocal slope" to the original slope. so, find the "m" value in your original equation (it's -4, right? )

original slope: m = -4   perpendicular slope: change the sign to its opposite and find the reciprocal ("flip" the number)

new slope is now positive (b/c the original slope was negative 4), and it's 1/4 (not the original slope of 4 or 4/1)