1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Oksana_A [137]
3 years ago
8

What are the roots of the equation x^2+3x-18=0

Mathematics
1 answer:
belka [17]3 years ago
8 0
First you open 2 parenthesis with x in each one:

(x )(x )=0

Then, you place the sign of the second term (the x term) in the first parenthesis.

(x+ )(x )=0

Next, you multiply the signs of the x term and the sign of the constant (the third term).
Since + × - = -, then you place a -.

(x+ )(x- )=0

You look at the constant (-18) and the second term (3). What two numbers multiplied give you -18 but subtracted (since the signs inside the parenthesis are opposite) give you 3? Those numbers are 6 and 3.
Since the result of the substraction need to be 3, you place the 6 with the + sign and the 3 with the negative sign (if you think of it, 6-3=3 but 3-6 = -3. That's the reason behind placing the numbers)

(x+6)(x-3)=0

Therefore,

x+6=0 or x-3=0

x=-6 or x=3

Your roots are -6 and 3.
You might be interested in
Can someone help me with this?
Natasha2012 [34]

Answer: X can not be 11 or higher, so that means this problem will be 10 or lower. There for the value of X=6

Step-by-step explanation:

4 0
3 years ago
20. Based on student records, 25% of the students at a large high school have a
Elenna [48]

Answer:

(E) 0.71

Step-by-step explanation:

Let's call A the event that a student has GPA of 3.5 or better, A' the event that a student has GPA lower than 3.5, B the event that a student is enrolled in at least one AP class and B' the event that a student is not taking any AP class.

So, the  probability that the student has a GPA lower than 3.5 and is not taking any AP  classes is calculated as:

P(A'∩B') = 1 - P(A∪B)

it means that the students that have a GPA lower than 3.5 and are not taking any AP  classes are the complement of the students that have a GPA of 3.5 of better or are enrolled in at least one AP class.

Therefore, P(A∪B) is equal to:

P(A∪B) = P(A) + P(B) - P(A∩B)

Where the probability P(A) that a student has GPA of 3.5 or better is 0.25, the probability P(B) that a student is enrolled in at least one AP class is 0.16 and the probability P(A∩B) that a student has a GPA of 3.5 or better and is enrolled  in at least one AP class is 0.12

So, P(A∪B) is equal to:

P(A∪B) = P(A) + P(B) - P(A∩B)

P(A∪B) = 0.25 + 0.16 - 0.12

P(A∪B) = 0.29

Finally, P(A'∩B') is equal to:

P(A'∩B') = 1 - P(A∪B)

P(A'∩B') = 1 - 0.29

P(A'∩B') = 0.71

5 0
3 years ago
Read 2 more answers
In Spencer’s garden, the number of rose bushes is 7 less than 1.5 times the number of carnation bushes. If the number of carnati
adelina 88 [10]
If carnation bushes is c, then the expression representing the number of rose bushes would be...


1.5c - 7
5 0
3 years ago
Read 2 more answers
A type of cell triples every hour. If there are 5 cells initially, which function can be used to
laila [671]

Answer:

T(t) = 5(3)(t)

Step-by-step explanation:

There are 5 cells initially.

And it triple every hour.

So

T0 =5

T(t) = T0(3t)

Each cell has it's multipling factor because it's Will be multipling by 3 every hour

T(t) = 5(3)(t)

4 0
3 years ago
How do I solve this????
Arlecino [84]
Let's say the numbers are "a" and "b"
hmm say "a" is the smaller, and "b" the greater

so "b" is "4 more than 5 times" "a"

so... 5 times "a" is 5*a or 5a
4 more than "that", will be "that" + 4
or
5a + 4

so.. whatever "a" is, "b" is 5a+4

now, their sum is 22, as opposed to "zz" hehe

so       \bf \begin{cases}
a+b=22\\
--------------\\
\boxed{b}=5a+4\qquad thus\\
--------------\\
a+\boxed{5a+4}=22
\end{cases}

solve for "a", to see what the smaller one is

what's "b"?  well, b = 5a + 4
3 0
3 years ago
Other questions:
  • Help me find the volume please
    8·1 answer
  • Amanda and her best friend found some money buried in a field. They split the money evenly each getting 24.28. How much money di
    13·1 answer
  • If a frog can move 3/5 of a mile every hour than how many hours would it take to go 6 miles?
    6·2 answers
  • Find the volume of a sphere with a radius of 5 ft.
    12·2 answers
  • I need help Please!
    15·2 answers
  • The Burgesses use about 2 gallons of drinking water per day. If each water jug holds 5 gallons , how many jugs of water do they
    6·1 answer
  • The figure below shows three small circles, each
    5·1 answer
  • What are the steps you need to take to solve this equation?
    10·2 answers
  • Can someone help me please!!!
    14·2 answers
  • Solve for the variables and show work please
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!