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>
Answer:
87.92
Step-by-step explanation:
3.14(a²+ab)=
<em>Plugging in values for a and b</em>
3.14(4²+4×3)=
3.14(16+12)=
3.14(28)=
87.92
Answer:
B: 378 cm^2
Step-by-step explanation:
22 * 24 = 528
528 - (10 * 15) = 378
<h3>Answer: 1.15</h3>
==============================================================
Work Shown:
QR = 73
QP = 55
PR = x
Pythagorean Theorem
a^2 + b^2 = c^2
(QP)^2 + (PR)^2 = (QR)^2
(55)^2 + (x)^2 = (73)^2
3025 + x^2 = 5329
x^2 = 5329-3025
x^2 = 2304
x = sqrt(2304)
x = 48
PR = 48
----------
tan(angle) = opposite/adjacent
tan(R) = QP/PR
tan(R) = 55/48
tan(R) = 1.1458333 approximately
tan(R) = 1.15
