Susan measures the length of some items in feet but needs to convert them all to inches. She looks up each measurement in feet online to find the correct number of inches.
There is a proportional relationship between the number of feet, x, and the number of inches,
y.
x (feet) y (inches)
4.
48
6
72
7
84
8
96
What is the constant of proportionality? Write your answer as a whole number or decimal.
inches per foot

i dont know sorry

step-by-step explanation:

x^2 + 81

we can factor this using difference of square binomials.

rewrite the equation:

x^2 - (-81)

factor:

(a^2 - b^2) = (√a^2 + √b^2)(√a^2 - √b^2)

(x^2 - (-81) = (x + √-81)(x - √-81)

we can remove the - from under the radical by multiplying it by i.

(x^2 - (-81) = (x + i√81)(x - i√81)

(x^2 - (-81) = (x + 9i)(x - 9i)

we can check our answer by using foil:

x^2 - 9ix + 9ix - 81i^2

x^2 - 81^2

i^2 = -1

x^2 + 81

yes

step-by-step explanation:

(2x+3)(x+5)(x-4)