The quadratic formula is above.
You want each equation in standard form: ax^2 + bx + c = 0
I begin each problem by defining variables.
For instance 3. Is in standard form. X^2 -2x - 3 = 0. a = 1, b = -2, c = -3
Now use quadratic formula: x = [- b + or - sqrt(b^2 - 4ac)]\2a
Answer:
x + y = 36.....Equation 1
x = 7 + 2y...... Equation 2
Step-by-step explanation:
Let the number of:
Orange goldfish = x
Black gold fish = y
Anna has a total of 36 goldfish in her aquarium, some are orange and some are black.
x + y = 36.....Equation 1
The number of orange goldfish is 7 more than twice the number of black goldfish.
x = 7 + 2y...... Equation 2
We can rewrite this as:
x - 2y = 7..... Equation 2
The system of equations below that can be used to describe the number of black and orange goldfish in Anna's aquarium is :
x + y = 36.....Equation 1
x = 7 + 2y...... Equation 2
Answer:
72 square feet not covered
Step-by-step explanation:
100%-40% = 60%
60% of 120 = 0.6x120 = 72
9514 1404 393
Answer:
- 16,965 mm/min
- 90π ≈ 282.7 radians/min
Step-by-step explanation:
The circumference of the CD is ...
C = πd
C = π(120 mm) ≈ 376.99 mm
This is the distance a point on the edge of the CD will travel when making one revolution. It will travel 45 times this far when making 45 revolutions:
(376.99 mm/rev)(45 rev/min) ≈ 16,965 mm/min
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There are 2π radians in each revolution, so the angular speed is ...
(2π rad/rev)(45 rev/min) = 90π rad/min ≈ 282.7 rad/min
