Answer:
see explanation
Step-by-step explanation:
To find the roots factor the left side
x³ + 7x² + 12x = 0 ← factor out x from each term
x(x² + 7x + 12) = 0
x(x + 3)(x + 4) = 0
Equate each factor to zero and solve for x
x = 0
x + 3 = 0 ⇒ x = - 3
x + 4 = 0 ⇒ x = - 4
Roots are x = - 4, x = - 3, x = 0
Answer:
x greater than and equal to -7
Step-by-step explanation:
Parabola touches at -7 and is going straight towards all positive integers
Therefore the domain is all numbers greater than or equal to -7
Answer:
a) linear. Cost per minute is a constant.
b) f(x) = 40 -0.15x
d) f(100) = 25. The remaining value is $25 after using 100 minutes.
Step-by-step explanation:
a) Since the cost per minute is a constant, the remaining dollar value of the phone decreases by the same amount for each minute used. The cost as a function of minutes used is a linear function with a constant rate of change.
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b) The value starts at $40 and decreases by $0.15 for each increment of x (minutes used). The function can be written as ...
f(x) = 40 -0.15x
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d) Put 100 where x is in the function definition and do the arithmetic.
f(100) = 40 -0.15×100 = 40 -15
f(100) = 25
According to the variable and function definitions, x=100 means 100 minutes have been used; f(x) = 25 means the remaining value of the phone is 25 dollars.
f(100) = 25 means the phone's remaining value is $25 when 100 minutes have been used.
Let x = the number of penguins we are finding
x ÷ 100 × 30 = 15
x = 15 ÷ 30 × 100
x = 50
hope this helps and have a great day :)
Answer:
b=−5x+y
Step-by-step explanation:
Let's solve for b.
y=5x+b
Step 1: Flip the equation.
b+5x=y
Step 2: Add -5x to both sides.
b+5x+−5x=y+−5x
b=−5x+y