Answer:
x
=
2
±
√
7
Explanation:
there are no whole numbers which multiply to - 3
and sum to - 4
we can solve using the method of
completing the square
the coefficient of the
x
2
term is 1
∙
add subtract
(
1
2
coefficient of the x-term
)
2 to
x2
−
4
x
⇒
x
2
+2(−
2
)
x
+
4
−
4
−
3
=
0
⇒
(
x
−
2
)2
−
7
=0
⇒
(
x
−
2
)
2
=
7
take the square root of both sides
⇒
x
−
2
=
±
√
7
←
note plus or minus
⇒
x
=
2
±
√
7←
exact solutions
Answer: 133.69 or 133.7
Step-by-step explanation:
Answer:
B)
Step-by-step explanation:
The formula for the area of a circle is :
The radius of a circle is the length from one side to the centre.
To work this out you would have to multiply pi by the radius of 7 squared, this gives you 153.94, however if using pi as in 3.14, then the answer is 153.86.
1) Multiply pi by 7 squared.
Answer:
Circumference is 43.98 inches
Step-by-step explanation:
Circumference = 2πr
= 2×3.14 ×7
= 43.98
Let the width be x.
width = x
length = x + 8
The area is 20 ft²
x(x + 8) = 20
x² + 8x = 20
x² + 8x - 20 = 0
(x + 10) (x - 2) = 0
x = -10 (rejected) or x = 2
Width = x = 2 ft
Length = x + 8 = 2 + 8 = 10 ft
Answer: The width is 2 ft and the length is 10ft.