The vertex is exactly half way between directrix and focus. In this case the vertex is (8,-7)
(h,k)
P is the distance between the vertex and either the directrix or focus, in this case p = 1.
a = 1/(4p) or 1/(4*1) or 1/4
write the equation in vertex form
y = a(x-h)^2 + k
y = 1/4(x-8)^2 -7
Answer:
Step-by-step explanation:
Isolate the variable, a. Note the equal sign, what you do to one side, you do to the other. Do the opposite of PEMDAS.
PEMDAS is the order of operation and stands for:
Parenthesis
Exponents (& Roots)
Multiplication
Division
Addition
Subtraction
First, add 3 to both sides of the equation:
u = -3a - 3
u (+3) = -3a - 3 (+3)
u + 3 = -3a
Next, divide -3 from both sides of the equation:
(u + 3)/-3 = (-3a)/-3
a = (u + 3)/-3
is your answer.
~
Similar triangles so AC:BC=AE:DE
15+6=21 = AE
15:12.5=21:?
to get from 15 to 12.5 you divide by 15 and times by 12.5 so do this the to the other side
21/15=1.4
1.4 x 12.5=17.5
So DE=17.5
Answer:
the pattern is +2, +6, +10, +14, +18 etc
so its in increment of 4
the rest is trivial
Step-by-step explanation:
