tom sold half of his comic books and then bought six more. he now has 12. how many did he begin with?
Answers
Sold half of book: b/2
Bought six more: b/2+
Now has 12: b/2+6=12
Subtract 6 on both sides: b/2+6-6=12-6
b/2=6
Multiply both sides by 2: b=12
Answer= 12 books
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A prize wheel at a carnival has eight spaces, and is equally likely to land on any of them. Four of the spaces give out a sticker, two of the spaces give out a pair of sunglasses, one of the spaces gives out a gift card, and one of the spaces gives out a water bottle. What is the probability of winning a pair of sunglasses on the first spin and a gift card on the second spin?
Which is greater -6 or -3
Answers
x+y = 9 ⇒ x = 9-y
x·y = -42
(9-y)·y = -42
9y-y² = -42
y²-9y-42 = 0 for a = 1, b = -9 e c = -42
Δ = b²-4ac
Δ = (-9)²-4(1)(-42)
Δ = 81+168
Δ = 249
y₁ = (-b+√Δ)/2a = (-(-9)+√249)/2(1) = (9+√249)/2 = 9/2 + √249/2
y₂ = (-b-√Δ)/2a = (-(-9)-√249)/2(1) = (9-√249)/2 = 9/2 - √249/2
For y = 9/2 + √249/2
x+y = 9
x = 9-y
x = 9-(9/2 + √249/2)
x = 9/2 - √249/2
For y = 9/2 - √249/2
x+y = 9
x = 9-y
x = 9-(9/2 - √249/2)
x = 9/2 + √249/2
Answer:
Numbers: 9/2 + √249/2 and 9/2 - √249/2
–10
–9
–8
–7
Answers
4x-12<=16+8x==> -28<=4x==>x>=-7
-7 is the only value in the set.
Answer D
Answer:
its -7 GG's to all
Step-by-step explanation:
Answers
Answers
33x^3/10 - 2x^2
Answers
Answer:The Phillips family used their sprinklers for 20 hours while The Petersons family used their sprinklers for 15 hours.
Step-by-step explanation:
Let x = the number of times that the Phillips family used their sprinkler last summer.
Let y = the number of times that the Petersons family used their sprinkler last summer.
The water output rate for the Phillips family sprinkler was 35 L per hour.
This means that the total volume of water from their sprinkler is 35xL
The water output rate for the Petersons family sprinkler was 15 L per hour.
This means that the total volume of water from their sprinkler is 15yL
The families used their sprinklers for a combined total of 35 hours, resulting in a total water output of 925 L. This means
x + y = 35
35x + 15y = 925 - - - - - - - - 2
Substituting x = 35 - y into equation 2
35(35-y) + 15y = 925
1225 - 35y + 15y = 925
- 20y = 925 - 1225 =- 300
y = - 300 / -20 = 15
x = 35 - y = 35 - 15 = 20
The Phillips family used their sprinklers for 20 hours while The Petersons family used their sprinklers for 15 hours.
The diameter of a cylinder is 6 feet 6 inches. The height of a cylinder is 12 feet 3 inches. What is the surface area? (feet squared) What is the volume? (feet cubed)