Answer:
x = - 2 or x = 5
Step-by-step explanation:
Given
3x² - 9x - 30 = 0 ← in standard form
Divide all terms by 3
x² - 3x - 10 = 0
To factor the quadratic
Consider the factors of the constant term (- 10) which sum to give the coefficient of the x- term (- 3)
The factors are - 5 and + 2, since
- 5 × 2 = - 10 and - 5 + 2 = - 3, thus
x² - 3x - 10 = 0
(x - 5)(x + 2) = 0
Equate each factor to zero and solve for x
x - 5 = 0 ⇒ x = 5
x + 2 = 0 ⇒ x = - 2
Answer:
Step-by-step explanation:
Amount of water in tank 1 = amount of water in tank 2
30t +25 = -20t + 1000
Add 20t to both sides
30t + 20t + 25 = -20t + 20t + 1000
50t + 25 = 1000
Subtract 25 from both sides
50t + 25 - 25 = 1000 - 25
50t = 975
Divide both sides by 50
t = 975/50 = 39/2
t = 19 minutes 30 seconds
After 19 1/2 minutes both tanks will have 610 liters of water
Answer:
You can tell because, as x increases/decreases, y increases/decreases at the same rate EACH TIME. This way, no matter how many times the proportions increase OR decrease, the ratio between x and y always stays the same.
Im not sure, when in doubt pick C
Answer:
72/4=18 so she could make their lunch for 18 days
Step-by-step explanation:
so it would be 6x12 for the bagels which would be 72
for the apples it would be 8x9 which is 72
the cookies would be 12x6 to get 72
and the juice boxes would be 9x8 to get 72
divide that by 4 to get 18
