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>
Triangles with a 90 degree angle. We use the sine, cosine and tangent functions to determine the missing angles and sides.
Answer:
.5, sqrt 14, 4
Step-by-step explanation:
.5, 3.7416, 4
Mark owes sally 85.00$ he finds 14 friends to help him pay her back. How much does each friend need to pay? (This includes mark)
Step-by-step explanation:
That is because 1/3 is not exactly equal to 0.333333. 0.333333 is a rounded number from the real number which 0.3 and the 3 goes on forever. In the image it show the the answer, in where the 3 goes on forever.
