a = 4, b = -21, c = -18
to keep from getting "mixed up", evaluate the discriminant first ...
b<sup>2</sup> - 4ac = (-21)<sup>2</sup> - 4(4)(-18) = 729
sqrt(729) = 27
x = (21 +/- 27)/8
x = -3/4, x = 6
since the discriminant is a perfect square, the original quadratic will factor ...
4x<sup>2</sup> - 21x - 18 = 0
(4x + 3)(x - 6) = 0
x = -3/4, x = 6
Answer:
the original price of the book is $20
Step-by-step explanation:
sometimes in a question, they put things in the question that don't actually help us get to the answer. usually we ignore it, but i'm going to list them out just to help you a bit more.
<u>Things that are useless:</u>
- his name is Jarred (his name could be gary, it doesn't affect us getting the answer)
- he went to a bookstore (he could've gone to the library, it wont affect us getting to the answer)
- the book is softcover (it could be any type of book, wont affect us getting to the answer)
- the item is a book (it could be anything that he bought, wont affect us getting to the answer.)
<u>Things that are helpful:</u>
- the book was on sale (helps us know that the price was reduced)
- the book was on sale 10% (helps us know how much it was reduced by)
- he spent $18 for the reduced price (helps us know how much he spent)
Ok, now that we know those, let's work on the question.
let b be the original book price
we need to find 10% so we have to use 90% (because 100 - 10 = 90)
if we needed to find 20% we would use 80% (because 100 - 20 = 80)
and so on.
90% of b = 18 (90% of the og. book price equals 18)
90/100 × b = 18 (write a correct equation and make the percent a fraction)
9/10 × b = 18 (simplify both sides of the equation)
9 × b = 180 (multiply both sides of the equation to get rid of fraction)
b = 20 (divide both sides of the equ. to get b by itself)
the original price of the book is $20
hope this helped :D
good luck my friend
- cheesetoasty
So, the value of x is 1.19
The question is an exponential equation
<h3>What is an exponential equation?</h3>
An exponential equation is a mathematical expression between two quantities in which one variable is raised to a power of the other variable.
<h3>How to find x?</h3>
Since 
,
Dividing through by 4ˣ, we have
Let y = (3/2)ˣ
So,
1 + y = y²
y² - y - 1 = 0
Using the quadratic formula to find y,
where a = 1 b = -1 and c = -1
Substituting the values of the variables into the equation, we have
Since y = (3/2)ˣ
Takung logarithm of both sides, we have
㏒y = ㏒(3/2)ˣ
㏒y = x㏒(3/2)
x = ㏒y/㏒(3/2)
x = ㏒y/㏒1.5
Since we do not have logarithm of a negative number, we use y = 1.618.
So, x = ㏒y/㏒1.5
x = ㏒1.618/㏒1.5
x = 0.2090/0.1761
x = 1.19
So, the value of x is 1.19
Learn more about exponential equation here:
brainly.com/question/11832081
#SPJ1
Complete question is;
Maya is choosing between several pay plans for her new job. If she usually has monthly sales of about $5,000, which plan would allow Maya to earn the most money in a month?
Plan, Monthly base salary, Commission rate
A, $500, 8%
B, $600, 7%
C, $700, 6%
D, $800, 5%
Options:
A. plan A
B. plan B
C. plan C
D. plan D
Answer:
Option D - Plan D
Step-by-step explanation:
For plan A, at 8% commission rate,her monthly pay would be, 500 + 8%*5,000 = $900
For plan B, at 7% commission rate, her monthly pay would be; 600 + 7%*5,000 = $950
For plan C, at 6% commission rate, her monthly pay would be;700 + 6%*5,000 = $1000
For plan D, at 5% monthly commission rate, her monthly pay = 800 + 5%*5,000 = $1050
So the plan that allows maya earn the most is the highest which is plan D
It should be around 13 percent I am not totally sure
