I think it's A because of PEMDAS so you multiply 8 by n-3
Answer:
81
Step-by-step explanation:
1. your leading coefficient has to be 1 (nothing before the x^2). If there is you have to divide that out before you start.
2. Move your constant (the number without any x attached) to the other side of the equation
3. take 1/2 of the b term (the one with the x attached) and then square it and then add it to both sides
4. Factor the left side
5. Set each factor equal to 0 and solve
Here is an example:
4x^2-24x+20=0
The first term is not a 1 so we have to divide it out by 4 first
x^2-6x+5=0
Move the 5 to the other side. It becomes negative.
x^2-6x=-5
Take 1/2 of 6 (3) then square it (9) and add it to both sides.
x^2-6x+9=-5+9
Factor the left side
(x-3)(x-3)=4
(x-3)^2=4
To solve you need to square root both sides
x-3=+/-
x-3=+/-2
x=3+2=5
x=3-2=1
Those would be your two answers.
<span>Hope that helps</span>
(x,y) = (r,16)
With this knowledge, plug in r for x, and 16 for y
16 = 2(r) - 4
Isolate the r, add 4 to both sides
16 (+4) = 2r - 4 (+4)
20 = 2r
Divide 2 from both sides
20/2 = 2r/2
r = 20/2
r = 10
hope this helps
