X or Y diagram is the answer to this question
ax² + bx + c = 0
x = (-b ± √(b² - 4ac))/2a
First, rewrite the first equation so that the first coefficient is 1. Divide everything by a.
(ax² + bx + c = 0)/a =
x² + (b/a)x + (c/a) = 0
Isolate (c/a) by subtracting (c/a) from both sides
x² + (b/a)x + (c/a) (-(c/a) = 0 (- (c/a)
x² + (b/a)x = 0 - (c/a)
Add spaces
x² + (b/a)x = -c/a
Take 1/2 of the middle term's coefficient and square it. Remember that what you add to one side, you add to the other.
x² + (b/a)x + (b/2a)² = -c/a + (b/2a)²
Simplify the left side of the equation.
x² + (b/a)x + (b/2a)² = (x + (b/2a))²
(x + b/2a))² = ((b²/4a²) - (4ac/4a²)) -> ((b² - 4ac)/(4a²))
Take the square root of both sides of the equation
√(x + b/2a))² = √((b²/4a²) - (4ac/4a²))
x + b/(2a) = (±√(b² - 4ac)/2a
Simplify. Isolate the x.
x = -(b/2a) ± (∛b² - 4ac)/2a = (-b ± √(b² - 4ac))/2a
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Answer:
The mean is 4.88 hours / day
Step-by-step explanation:
To calculate the mean we just add the values and divide by the number of items (in this case we add the hours and divide by the number of days)
so the equation would be
<span>We have to use PEMDAS for this expression.
Parentheses
Exponents
Multiplication
Division
Addition
Subtraction
</span>(2x^2 - 5x + 4) Original Mathematical Expression
[2(7)^2 - 5(7) + 4] Plugging the value of x, 7 into expression.
There are parentheses, so that means we have to work in them.
There are exponents, so we have to do those first.
[2(49) - 5(7) +4] Exponents.
There is multiplication, that we can do, so we do that left to right.
[98 - 35 + 4] Multiplication.
There is no division.
There is addition and subtraction, so we do those left to right.
[63 + 4] Subtraction.
67 Addition.
Final Answer: 67
