Assuming that there are plus signs between the 6, 2, and 9 the answer is 21x+20
Answer:The second choice is the correct one
Explanation:(2x+3)^2 + 8(2x+3) + 11 = 0
To use the u substitution, we will assume that:
2x + 3 = u
Substitute with this in the given expression, we will get:
u^2 + 8u + 11 = 0
The general form of the second degree equation is:
ax^2 + bx + c = 0
Comparing the expression we reached with the general one, we will find that:
a = 1
b = 8
c = 11
The roots can be found using the rule found in the attached picture.
This means that, for the given expression:
u = -4 ± √5
Now, we have:
u = 2x+3
This means that:
at u = -4 + √5
2x + 3 = -4 + √5
2x = -7 + √5
x = (-7 + √5) / 2
at u = -4 - √5
2x + 3 = -4 - √5
2x = -7 - √5
x = (-7 - √5) / 2
This means that, for the given expression:
x = (-7 ± √5 ) / 2
Hope this helps :)
Answer:
2 1/8
Step-by-step explanation:
Hope this helps!!
Answer:
Length = 10 inches
Width = 10 inches
Step-by-step explanation:
The perimeter of the base is 40 inches, so we can write the following equation:
2*Length + 2*Width = 40
Length + Width = 20 (eq1)
The volume of the box is 800 in3, so we have:
800 = Length*Width*8
Length*Width = 100 (eq2)
From the (eq1), we have:
Length = 20 - Width
Using this value of Length in (eq2), we have:
(20 - Width)*Width = 100
20*Width - Width^2 - 100 = 0
Using Bhaskara's formula, we have:
Delta = b^2 - 4ac = 400 - 400 = 0
Width = -b/2a = -20/(-2) = 10 inches
Length = 20 - Width = 20 - 10 = 10 inches
So the length is 10 inches and the width is 10 inches
Answer:
y
=
8
Step-by-step explanation:
Explanation:
the initial statement is
y
∝
x
to convert to an equation multiply by k the constant
of variation
⇒
y
=
k
x
to find k, use the given condition for x and y
y
=
10
when
x
=
5
y
=
k
x
⇒
k
=
y
x
=
10
5
=
2
the equation is
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
∣
∣
∣
2
2
y
=
2
x
2
2
∣
∣
∣
−−−−−−−−−−−
x
=
4
→
y
=
2
×
4
=
8