A = 57
45 + 12 = 57
57 - (-12) = 45
Answer:
No
Step-by-step explanation:
If the lines are perpendicular then they will be the negative reciprocals of each other.
Calculate the slope using the slope formula
m = (y₂ - y₁ ) / (x₂ - x₁ )
with (x₁, y₁ ) = P(- 8, - 10) and (x₂, y₂ ) = Q(- 5, - 12)
= 
= - 
Repeat the process with
(x₁, y₁ ) = R(9, - 6) and (x₂, y₂ ) = S(17, - 5)
= 
= 
The slopes are not the negative reciprocal of each other, thus they are not perpendicular.
I assume that the parabola in this particular problem is one whose axis of symmetry is parallel to the y axis. The formula we're going to use in this case is (x-h)2=4p(y-k). We know variables h and k from the vertex (1,20) but p is not given. However, we can solve for p by substituting values x and y in the formula with the y-intercept:
(0-1)^2=4p(16-20)
Solving for p, p=-1/16.
Going back to the formula, we can finally solve for the x-intercepts. Simply fill in variables p, h and k then set y to zero:
(x-1)^2=4(-1/16)(0-20)
(x-1)^2=5
x-1=(+-)sqrt(5)
x=(+-)sqrt(5)+1
Here, we have two values of x
x=sqrt(5)+1 and
x=-sqrt(5)+1
thus, the answers are: (sqrt(5)+1,0) and (-sqrt(5)+1,0).
