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)
Perpendicular lines have slopes that multiply to get -1
y=mx+b is the slope intercept equation
m=slope
so get into y=mx+b form
-x+2y=4
solve for y
add x both sides
2y=x+4
divide by 2 both sides
y=(1/2)x+2
the slope is 1/2
perppendicular line slope multiplies to -1
1/2 times what=-1
times 2/1 both sides
what=-2/1=-2
y=-2x+b
find b
we are given a point is (-2,1)
when x=-2, y=1
1=-2(-2)+b
1=4+b
minus 3 both sides
-3=b
so the equation is
y=-2x-3
your teacher might want it in standard form (ax+by=c) so
add 2x both sides
2x+y=-3 is an equation
so y=-2x-3 is correct (slope intercept form)
2x+y=-3 is also correct (standard form)
The answer is 65 if your wondering why you have to put the numbers from least to greatest then find the one that is in the middle