Answer:
x=1 or x=−9
Step-by-step explanation:
Let's solve your equation step-by-step.
x(x+8)=9
Step 1: Simplify both sides of the equation.
x2+8x=9
Step 2: Subtract 9 from both sides.
x2+8x−9=9−9
x2+8x−9=0
Step 3: Factor left side of equation.
(x−1)(x+9)=0
Step 4: Set factors equal to 0.
x−1=0 or x+9=0
x=1 or x=−9
Answer:
7 is not a solution for x.
Step-by-step explanation:
To see if 7 is a solution for x, we will simply plug in the value for x and see if the left hand side is equal to the right hand side.
3x + 8 - x = 57 - 4
3(7) + 8 - (7) ?= 57 - 4
21 + 8 - 7 ?= 53
29 - 7 ?= 53
22 ?= 53 (( NO ))
Since 22 does not equal 53, 7 is not a solution for x.
Let's find the solution for x:
3x + 8 - x = 57 - 4
2x + 8 = 53
2x = 45
x = 22.5
Let's validate this solution for x:
3x + 8 - (x) = 57 - 4
3(22.5) + 8 - (22.5) ?= 57 - 4
67.5 + 8 - 22.5 ?= 53
45 + 8 ?= 53
53 == 53 (( YES ))
Since 53 is indeed equal to 53, then 22.5 is a solution for x.
Cheers.
Answer:
Area of the rectangle = 144 square inches
Step-by-step explanation:
Area of a rectangle = length × width
Width = 4 inches
Length = 3 feet
1 feet = 12 inches
3 feet = 36 inches
Area of a rectangle = length × width
= 36 inches × 4 inches
= 144 square inches
Therefore,
Area of the rectangle = 144 square inches
Answer and Step-by-step explanation:
we have the following data:
Point estimate = sample mean = \ bar x = 12.39
Population standard deviation = \ sigma = 3.7
Sample size = n = 177
a) the margin of error with a 90% confidence interval
α = 1 - 90%
alpha = 1 - 0.90 = 0.10
alpha / 2 = 0.05
Z \ alpha / 2 = Z0.05 = 1,645
Margin of error = E = Z \ alpha / 2 * (\ sigma / \ sqrtn)
we replace:
E = 1.645 * (3.7 / \ sqrt177)
Outcome:
E = 0.46
b) margin of error with a 99% confidence interval
α = 1-99%
alpha = 1 - 0.99 = 0.01
alpha / 2 = 0.005
Z \ alpha / 2 = Z0.005 = 2,576
Margin of error = E = Z \ alpha / 2 * (\ sigma / \ sqrtn)
we replace:
E = 2,576 * (3.7 / \ sqrt177)
Outcome:
E = 0.72
c) A larger confidence interval value will increase the margin of error.
B
the other options all have a set price, the answers in b could all change price from month to month