Answer:
Option D is the correct answer
Step-by-step explanation:
The x intercepts of the parabola are the solutions of the equation. These points can be determined either by graphical method or by solving the quadratic equation with any of the methods of solving a quadratic equation.
In order to use the graphical method, values of x are picked and substituted into the equation to get corresponding values of y. The y values are plotted against the x axis and the parabola (downward) is drawn. The points where it cuts the horizontal axis become the solutions of the equation
y = x^2 - 9x + 18
Solving the equation by using the factorization method,
x^2 - 9x + 18 = 0
x^2 - 6x - 3x + 18 = 0
x(x-6)-3(x-6)
(x-6)(x-3) = 0
x -6 = 0 or x -3 = 0
x = 6 or x = 3
The x-intercepts are (3, 0) and (6, 0)
Answer:
Below.
Step-by-step explanation:
To find the number of students in each grade you multiply the marks by the frequency density. The number of students is given by the area under the rectangles.
So to find the number of students with grade U (< 160) it is:
120 * 0.2 + 40*0.5
= 24 + 20
= 44.
The number for Grade E
= (200 - 160) * 0.5
= 40 * 0.5
= 20.
The others can be found in the same way.
Variables are symbols that are used to represent a number in an expression or equation.
There's one word phrase here, and it's answer is: c*3
If you need help with another one, just let me know! :)
