All categories

2 years ago

Help please!! i don’t understand this one!

Mathematics

1 answer:

12345 [234]2 years ago

5 0

Answer:

C, D

Step-by-step explanation:

This equation can be solved any of several ways. One that doesn't require much thought is using the quadratic formula.

For ax² +bx +c = 0, the solutions are ...

$x=\dfrac{-b\pm\sqrt{b^2-4ac}}{2a}$

In the given equation, a=2, b=11, c=5, so this becomes ...

$x=\dfrac{-11\pm\sqrt{11^2-4\cdot2\cdot5}}{2\cdot2}=\dfrac{-11\pm\sqrt{81}}{4}\\\\x=\dfrac{-11\pm9}{4}=\left\{-\dfrac{20}{4},-\dfrac{2}{4}\right\}=\{-5,-\frac{1}{2}\}$

The solutions are ...

C. x = -5

D. x = -1/2

_____

My personal favorite is using a graphing calculator. The solutions are the x-intercepts of the expression on the left. That is, where its value is zero, as the equation says.

You might be interested in

All freshmen, sophomores, juniors, and seniors attended a

Trava [24]

Answer:

The probability is .034375 or 11/320

Step-by-step explanation:

the probability of a senior being chose first is 22 (seniors) divided my total number of students (80) is .275 percent.

multiplied by the probability of a sophomore being chosen 10/80 which equals .125.

multiply those together and you get your probability. 0.034375 or 11/320

5 0

2 years ago

Read 2 more answers

I don't get the subject of congruent triangles. How do I figure out if there's not enough information to know if it is congruent

babymother [125]

Answer:

Okay, there are many ways to find if a triangle is congruent.

Let's start with some different terminology.

For the sake of simplicity let us say that S stands for when a side is congruent for both triangles and A stands for when an angle (<) is congruent between both the triangles as well.

So, you need to memorize some rules. If you find that 2 triangles are congruent in the sense of; SSS, SAS, AAS, SAA, and ASA. One thing to remember is that Angle Side Side isn't congruent and is called <em>Donkey Theorem</em>. This theorem only works for right triangles.

One way to know if your triangle isn't congruent is if you can find a part of the triangle that is different.

I know that wasn't the best explanation but I hope it helped anyhow. :)

5 0

2 years ago

castortr0y [4]

Answer:

Its an Arithmetic progression

Step-by-step explanation:

d1= -18-(-25)= 7

d2= -11-(-18)= 7

d1 = d2

r1 = -18/25=0.72

r2 = -11/-8= 0.611

r1 isnt = r2

4 0

1 year ago

A retailer allows 15% discount on the Marked price of an electric fan. If a customer pays Rs 2244 with 10% VAT,find the Marked P

Alona [7]

Answer:

2400

Step-by-step explanation:

2244 is the final price. it includes the VAT based on the actual sale price. and that is then actually 15% lower than the originally marked price.

so, let's calculate backwards :

2244 = 100% sale price + 10% VAT = 110%

1% = 2244 / 110 = 20.40

100% (actual sale price) = 20.40×100 = 2040

now, because of the 15% discount, these 2040 are only 85% of the originally marked price.

2040 = 85%

1% = 2040 / 85 = 24.00

100% (the original marked price) = 24×100 = 2400

5 0

2 years ago

Hunter had seven gallons of water in the refrigerator. Of those, two and one-fourth gallons were spring water and one and one-fi

Crank

Answer:

3 11/20

Step-by-step explanation:

Total gallons of water=7

Spring water=two and one-fourth gallon=2 1/4

Filtered water=one and one-fifth

=1 1/5

Spring water+filtered water=2 1/4 + 1 1/5

=9/4+6/5

= 45+24/20

=69/20

=3 9/20

How many gallons of water were not spring or filtered

=Total gallons- (spring+ filtered water)

=7-69/20

=140-69/20

=71/20

=3 11/20

5 0

2 years ago