Answer:
Step-by-step explanation:
y = x² + x - 3
x = - 3
y = ( - 3 )² + ( - 3 ) - 3 = 3
( - 3 , <em>3</em> )
x = 0 ⇒ y = - 3
( 0 , <em>- 3</em> )
x = 1
y = ( 1 )² + ( 1 ) - 3 = - 1
( 1 , <em>- 1 </em>)
<em>(b).</em> Coordinate x of the vertex of quadratic equation y = ax² + bx + c is
-
x = - = -
= - 0.5
y = ( - 0.5 )² + ( - 0.5 ) - 3 = - 3.25 = - 3
( - , - 3
)
Answer:
The correct option is A
A) -10 ≤ x ≤ 10 , -10 ≤ y ≤ 10
Step-by-step explanation:
We have been given a system of equation:
y = -13x + 17
y = 5x - 23
We have to determine the best window range from the following options:
A) -10 ≤ x ≤ 10 , -10 ≤ y ≤ 10
B) -20 ≤ x ≤ 0 , -20 ≤ y ≤ 0
C) 0 ≤ x ≤ 20, 0 ≤ y ≤ 20
D) 20 ≤ x ≤ 40 , 20 ≤ y ≤ 40
The graph of both the equation is attached below, we can see that the graph shows the solution at the point (2.222, -11.869), where x is positive and y is negative
Now consider the options
Option A includes the solution
Option B doesn't show positive values for x
Option C doesn't show negative values for y
Option D doesn't include the x or y part of the solution
something noteworthy is that the squared variable is the "x", thus the parabola is a vertical one, the "p" value is negative, so is opening downwards, and the h,k is pretty much the origin,
vertex is at (0,0)
the focus point is "p" or 5 units down from there, namely at (0, -5)
the directrix is "p" units on the opposite direction, up, namely at y = 5
the focal width, well, |4p| is pretty much the focal width, in this case, is simply yeap, you guessed it, 20.