Answer: 13n + 20
Step-by-step explanation:
The cost of each book is $13. That means that if you end up buying "n" books, cost would be:
= Cost of each book * number of books
= 13 * n
= 13n
You would also get charged a flat rate for shipping of $20 which would be added to the above cost to bring a total of:
= 13n + 20
<h3>Answer:</h3>
±12 (two answers)
<h3>Explanation:</h3>
Suppose one root is <em>a</em>. Then the other root will be -3<em>a</em>. The product of the two roots is the ratio of the constant coefficient to the leading coefficient:
(<em>a</em>)(-3<em>a</em>) = -27/4
<em>a</em>² = -27/(4·(-3)) = 9/4
<em>a</em> = ±√(9/4) = ±3/2
Then the other root is
-3<em>a</em> = -3(±3/2) = ±9/2 . . . . . . the roots will have opposite signs
We know the opposite of the sum of these roots will be the ratio of the linear term coefficient to the leading coefficient: b/4, so ...
-(a + (-3a)) = b/4
2a = b/4
b = 8a = 8·(±3/2)
b = ±12
_____
<em>Check</em>
For b = 12, the equation factors as ...
4x² +12x -27 = (2x -3)(2x +9) = 0
It has roots -9/2 and +3/2, the ratio of which is -3.
For b = -12, the equation factors as ...
4x² -12x -27 = (2x +3)(2x -9) = 0
It has roots 9/2 and -3/2, the ratio of which is -3.
(x²+4x-12)/(x-2)=0
(x+6)(x-2)/(x-2)=0
x+6=0
x=-6
(-6,0)
Answer:
Step-by-step explanation:
X + 4 > -15
x > -15 - 4
x > -19
The answer is: x > -19.
