The table shows the number of boys and girls who have come to the playground. help pleaseOutcome Boys Girls
Frequency 35 40

What is the experimental probability that the next person who comes to the playground will be a girl?

A.8/15

B.1/2

C.7/15

D.2/5

Answers

Answer 1

Answer: The right answer for the question that is being asked and shown above is that: "A.8/15." The table shows the number of boys and girls who have come to the playground. the experimental probability that the next person who comes to the playground will be a girl is A.8/15

f(x) = 2x² + x – 1

Further explanation

Discriminant of quadratic equation ( ax² + bx + c = 0 ) could be calculated by using :

D = b² - 4 a c

From the value of Discriminant , we know how many solutions the equation has by condition :

D < 0 → No Real Roots

D = 0 → One Real Root

D > 0 → Two Real Roots

Let us now tackle the problem!

An axis of symmetry of quadratic equation y = ax² + bx + c is :

$\large {\boxed {x = (-b)/(2a) } }$

Option 1 :

f(x) = 2x² + x – 1 → a = 2 , b = 1 , c = -1

Axis of symmetry → $x = (-b)/(2a) = (-1)/(2(2)) = -(1)/(4)$

Option 2 :

f(x) = 2x² – x + 1 → a = 2 , b = -1 , c = 1

Axis of symmetry → $x = (-b)/(2a) = (-(-1))/(2(2)) = (1)/(4)$

Option 3 :

f(x) = x² + 2x – 1 → a = 1 , b = 2 , c = -1

Axis of symmetry → $x = (-b)/(2a) = (-2)/(2(1)) = -1$

Option 4 :

f(x) = x² – 2x + 1 → a = 1 , b = -2 , c = 1

Axis of symmetry → $x = (-b)/(2a) = (-(-2))/(2(1)) = 1$

Learn more

Solving Quadratic Equations by Factoring : brainly.com/question/12182022
Determine the Discriminant : brainly.com/question/4600943
Formula of Quadratic Equations : brainly.com/question/3776858

Answer details

Grade: High School

Subject: Mathematics

Chapter: Quadratic Equations

Keywords: Quadratic , Equation , Discriminant , Real , Number

The graph of function $\boxed{f(x)=2x^(2)+x-1}$ has an axis of symmetry as $\boxed{x=-(1)/(4)}$ .

Further explanation:

The standard form of a quadratic equation is as follows:

$\boxed{f(x)=ax^(2)+bx+c}$

The vertex form of a quadratic equation is as follows:

$\boxed{g(x)=a(x-h)^(2)+k}$

Axis of symmetry is the line which divides the graph of the parabola in two perfect halves.

The formula for axis of symmetry of a quadratic function is given as follows:

$\boxed{x=-(b)/(2a)}$

The first function is given as follows:

$f(x)=2x^(2)+x-1$

The above function is in standard form with $a=2$ , $b=1$ and $c=-1$ .

Then its axis of symmetry is calculated as,

$\begin{aligned}x&=-(b)/(2a)\n&=-(1)/(2*2)\n&=-(1)/(4)\end{aligned}$

The axis of symmetry of first function is $x=-(1)/(4)$ .

Express the function $f(x)=2x^(2)+x-1$ in its vertex form,

$\begin{aligned}f(x)&=2x^(2)+x-1\n&=(√(2)x)^(2)+\left(2* √(2)x* (1)/(2√(2))\right)-1+\left((1)/(2√(2))\right)^(2)-\left((1)/(√(2))\right)^(2)\n&=\left(√(2)x+(1)/(2√(2))\right)^(2)-1-(1)/(8)\n&=\left[√(2)\left(x+(1)/(4)\right)\right]^(2)-(9)/(8)\n&=2\left(x-\left(-(1)/(4)\right)\right)^(2)-(9)/(8)\end{aligned}$