the first part isn't 90, it's 180.
the whole circle is 360, half of 360 is 180
an acute angle is any angle less than 90 degrees.
Hi, the answer is "You pay $11 for a movie ticket and some amount at the concession stand for a total of $28". We know this because the key words "total" before $28 dollars - 'total' stands for an equal sign in equations.
The unknown, or x, is the "some amount at the concession stand". This is an unknown value, but we do know it is added to $11 dollars for the movie ticket (which is a known value.)
Therefore, we have 11 (the movie ticket) plus (key word: and) some amount (meaning x) = (key word: total) 28
One expression could be.... Nine times 4 plus five equals forty one. ALSO... Eight times eight equals sixty four then subtract twenty four equals forty one
385.6 square feet is the answer
Step-by-step explanation:
From the statement:
M: is total to be memorized
A(t): the amount memorized.
The key issue is translate this statement as equation "rate at which a subject is memorized is assumed to be proportional to the amount that is left to be memorized"
memorizing rate is 
.
the amount that is left to be memorized can be expressed as the total minus the amount memorized, that is 
.
So we can write
And that would be the differential equation for A(t).
