Mai has been walking indoors because of cold temperatures. On Day 4 at noon, Mai hears a report that the temperature is only 9 degrees Fahrenheit. She remembers
the morning news reporting that the temperature had doubled since midnight and
was expected to rise 15 degrees by noon. Mai is pretty sure she can draw a diagram
to represent this situation but isn't sure if the equation is 9 = 15 + 21
or 2(1 + 15) = 9. What would you tell Mai about the diagram and the equation and
how they might be useful to find the temperature, 1, at midnight?

step-by-step explanation:

is their an equation anywhere i can take a   look at it and see if i am right.

can i see a photo of the question so i can you?

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

br tat so much r