The correct question is
<span>
Penelope determined the solutions of the quadratic function by completing the square.f(x) = 4x² + 8x + 1
–1 = 4x² + 8x
–1 = 4(x² + 2x)
–1 + 1 = 4(x² + 2x + 1)
0 = 4(x + 2)²
0 = (x + 2)²
0 = x + 2
–2 = x
What error did Penelope make in her work?
we have that
</span>f(x) = 4x² + 8x + 1
to find the solutions of the quadratic function
let
f(x)=0
4x² + 8x + 1=0
Group terms that contain the same variable, and move the
constant to the opposite side of the equation
(4x² + 8x)=-1
Factor the
leading coefficient
4*(x² + 2x)=-1
Complete the square Remember to balance the equation
by adding the same constants to each side.
4*(x² + 2x+1)=-1+4 --------> ( added 4 to both sides)
Rewrite as perfect squares
4*(x+1)²=3
(x+1)²=3/4--------> (+/-)[x+1]=√3/2
(+)[x+1]=√3/2---> x1=(√3/2)-1----> x1=(√3-2)/2
(-)[x+1]=√3/2----> x2=(-2-√3)/2
therefore
the answer is
<span>
Penelope should have added 4 to both sides instead of adding 1.</span>
9514 1404 393
Answer:
- 30m +50 = 20m +100
- m = 5
- yes. symmetric property of equality.
Step-by-step explanation:
1. The expression for c in the first equation is (30m+50). Substituting that for c in the equation ...
c = 20m +100
gives you ...
30m +50 = 20m +100
__
2. Adding -50-20m to both sides gives ...
10m = 50
m = 5 . . . . . . . divide by 10
__
3. Doing the substitution in reverse, you would substitute (20m+100) for c in the equation ...
c = 30m +50
to get ...
20m +100 = 30m +50
This is the equation of part 1 with the expressions swapped to the other side of the equal sign. The symmetric property of equality tells you that changing sides of the equal sign does not change the value of the variable(s).
You get the same solution.
Answer:
CA = 13.5
Step-by-step explanation:
tan 64 = CA/6.6
2.05 = CA/6.6
CA = 13.5
Answer:
<h2>4 terms</h2>
Step-by-step explanation:
Term 1: 5x^3
Term 2: 8x^2y
Term 3: 4xy
Term 4: 4