Use the quadratic formula to solve the equation x2+7x​


Answer 1

The solution of the equation x2+7x​ is 0, -7 using the quadratic formula.

Step-by-step explanation:

x2 + 7x = 0

-b  ± √ b2 - 4(ac)/ 2a


a = 1, b = 7, c = 0

= -7  ± √(7)2 - 4(1 x 0) / 2 x 1

= - 7   ± 7 / 2

x = 0 , -7

Related Questions


The Texas state sales and use tax is 6.25% Represent this quantity as a fraction and as a decimal


Decimal- . 0625

fraction- 6.25/100

The width of a rectangle is 8 cm less than its length. The perimeter of the rectangle is 52 cm.What is the width of the rectangle?


Let X be width of a rectangle, then
(x+8) - length

(x+x+8)*2 = 52
x+x+8 = 52/2
2x+8 = 26
2x = 26-8
2x = 18
x = 18/2
x = 9 cm

Answer: 9 cm.

Dr potter provides vaccinations against polio and measles. Each polio vaccination multi-dose vial consists of 44 individual doses, and each measles vaccination multi-dose consists of 22 individual doses. Last year, Dr. Potter used a total of 60 multi-dose vials that consisted of a total of 2024 individual doses. How many individual polio and measles vaccinations did Dr. Potter give respectively A) (28, 32) b) (32,28) c) 64,32 d) 14,28


Answer: b) (32,28)

Step-by-step explanation:

Let x be the number of polio individual doses and y be the number of each measles  individual doses.

Then the number of polio vaccination  = 44x

The number of measles  vaccination multi-dose = 22x

According to the question,

Dividing 22 on equation (2) both sides, we gwt

Subtract (1) from (3), we get

Substitute x=32 in equation (1), we get

Hence, Dr. Potter gives 32 individual polio vaccination and 28 individual measles vaccinations .

The correct answer for the question that is being presented above is this one: "b) (32,28)." Dr potter provides vaccinations against polio and measles. Each polio vaccination multi-dose vial consists of 44 individual doses, and each measles vaccination multi-dose consists of 22 individual doses.

NEED HELP ASAP! Which expressions are equivalent to the one below? Check all that apply. 5^x

A. 15^x/3^x

B. x^5

C. 5*5^x+1

D. (15/3)^x

E. 5*5^x-1




Serena asked her parents if for their picnic they could have 20% more portions of coca-cola than they planned, and if each portion could be 20% bigger. Her parents agreed. By what percent more coca cola will they buy?




Step-by-step explanation:

If p represents the number of portions and q represents the quantity in each portion, then the original amount needed was p·q.

After p is increased by 20%, its number is ...

p + 0.20·p = 1.20·p

After q is increased by 20%, its amount is ...

q + 0.20 ·q = 1.20·q

Then the new amount the parents must buy is ...

(1.20p)(1.20q) = 1.20²·pq = 1.44pq

This amount is ...

(1 + 44/100)·pq = pq + 44%·pq

It is 44% more than the original planned purchase.


44 percent

Step-by-step explanation:


what positive number satisfies the condition that twice the number minus three times the reciprocal of the number is equal to 1?



"twice the number minus three times the reciprocal of the number is equal to 1."
Let the number be n.  Then 2n - ------- = 1

Mult all 3 terms by n to elim. the fractions:

2n^2 - 3 = n.  Rearranging this, we get 2n^2 - n - 3 = 0.

We need to find the roots (zeros or solutions) of this quadratic equation.

Here a=2, b= -1 and c= -3.  Let's find the discriminant b^2-4ac first:

disc. = (-1)^2 - 4(2)(-3) = 1 + 24 = 25.

That's good, because 25 is a perfect square.
                -(-1) plus or minus 5         1 plus or minus 5
Then x = ------------------------------ = --------------------------
                            2(2)                                  4

x could be 6/4 = 3/2, or -5/4.

You must check both answers in the original equation.  If the equation is true for one or the other or for both, then you have found one or more solutions.

Why does 0.25 x 0.4 have a one decimal place in the product


The product of these numbers are 0.100
since 0.100 is same as 0.1
so there is only one decimal place

What are three kinds of insurance besides life and auto?



The correct answers are ''Home Insurance'', ''Fire Insurance'' and ''Social Insurance''.

Step-by-step explanation:

Homeowner's insurance is the name given to the type of insurance that covers the damage under a residence which representes the good that is being covered. Its policy combines differents personal insurance protections.

Fire insurance is the one type of insurance whose main focus is on to cover damaged and losses caused by fire. However this type of insurance contains certain type of exclusions in its policy terms which includes situation like war, nuclear risks and similiar.

Social Insurance is the type of insurance that is promoted by the government whose main characteristics are defined by an statute, it is funded generally by taxes and focus on a specific population.

Malpractice, Liability, Fire, and Homeowners' insurance are all different kinds of insurance besides Life and Automobile.

The equation 2x2 + 5x - 12 = 0 is factored. Each factor is set equal to zero. What are these two equations?


1. 2x-3=0    x=3/22. x+4=0x=-4


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