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>
#22. We are given that y = 1/4. So, we want to plug this value into the expression 15/y:
15/(1/4)
When you divide by a fraction, you should follow the rule “flip the guy and multiply”. Basically, 15/(1/4) = 15 * 4 = 60.
The answer for #22 is (D).
#23. We can use a proportion:
(The shaded area)/(entire circle area) = (360 - 60)/360
But, we don’t have to find the areas of the region and circle; we can just solve the fraction:
(360 - 60)/360 = 300/360 = 30/36 = 5/6
The answer for #23 is (A).
Answer:
180 in
Step-by-step explanation:
10*6*3=180
Answer:
I think c and d
Step-by-step explanation:
srry if im wrong
-512.
Type negative 8 to the third power in google. It really is the answer. :)
