Between what two consecutive numbers is the square root of 20

Choose the inverse of y = x2 - 10x.

PilotLPTM [1.2K]

=Y2-10Y

We move all terms to the left:

-(Y2-10Y)=0

We add all the numbers together, and all the variables

-(+Y^2-10Y)=0

We get rid of parentheses

-Y^2+10Y=0

We add all the numbers together, and all the variables

-1Y^2+10Y=0

a = -1; b = 10; c = 0;

Δ = b2-4ac

Δ = 102-4·(-1)·0

Δ = 100

The delta value is higher than zero, so the equation has two solutions

We use following formulas to calculate our solutions:

Y1=−b−Δ√2aY2=−b+Δ√2a

Δ‾‾√=100‾‾‾‾√=10

Y1=−b−Δ√2a=−(10)−102∗−1=−20−2=+10

Y2=−b+Δ√2a=−(10)+102∗−1=0−2=0

3 0

3 years ago

A group of 100 students took a quiz. Their average score was 76 points. If the average score for the boys was 80 points and the

sveta [45]

Answer:

The number of girls participated in quiz is 40 .

Step-by-step explanation:

Given as :

Total number of students took quiz = 100

Average score of 100 students = 76 points

The Average score of boys = 80 points

The Average score of girls = 70 points

Let The number of boys participated in quiz = b

Let The number of girls participate in quiz = g

Now, According to question'

Total number of students took quiz = number of boys participated in quiz + number of girls participated in quiz

Or, b + g = 100 ........A

Again

∵ Average score of 100 students = 76 points

∴ Total score of 100 students = 76 × 100 = 7600

So, Average score of boys × number of boys participated + Average score of girls × number of girls participated = Total score of 100 students

Or, b × 80 + g × 70 = 7600

Or, 80 b + 70 g = 7600 .........B

Now, Solving equation A and B

(80 b + 70 g ) - 70 ×( b + g ) = 7600 - 70 × 100

I.e (80 b - 70 b) + (70 g - 70 g) = 7600 - 7000

Or, 10 b + 0 = 600

∴ b = $\dfrac{600}{10}$

i.e b = 60

So, The number of boys participated in quiz = b = 60

Put the value of b into eq A

∵ b + g = 100

So, g = 100 - b

Or, g = 100 - 60

i.e g = 40

So, The number of girls participated in quiz = g = 40

Hence, The number of girls participated in quiz is 40 . Answer

6 0

3 years ago

Drove that sinA+ sin5=2 sin A +5/2 COSA -5/2

const2013 [10]

Put it in a more simplified form

6 0

2 years ago

If y=3x - 5, find the value of y when x = -1

Tpy6a [65]

y=3x-5

x=-1

y=3*(-1)-5=-3-5=-8

y=-8

5 0

3 years ago

Read 2 more answers

Will adding a negative number to another integer always result in a negative sum? Why?

Ghella [55]

Answer:

D No, the integer with the larger absolute value always determines the sign of the sum.

Step-by-step explanation:

Suppose the integer you start with is +3. Adding -1 or -2 or -3 to that will result in 2, 1, or 0, none of which are negative. Only when you add a negative number with an absolute value greater than 3 will you get a sum that is negative. That is, the number in the sum that has the largest absolute value determines the sign of the result. (This is most important when the signs differ, but it is also true when the signs are the same.)

7 0

3 years ago