What is the sum of all values that satisfy the equation 3x2 + 30x + 15...
The simplest way to solve this problem is to use the theorem that any quadratic equation in the form ax
2 + bx + c = 0 has two (possibly equal) solutions that have a sum of -b/a and a product of c/a. Therefore the sum of the solutions to this equation is -30/3 = -10.
If you don't recall this theorem, you can solve it the hard way: by finding the two solutions with the Quadratic Formula and adding them together.
Use the quadratic formula,
Simplify:
Simplify the radical:
Reduce the fractions:
The two solutions are x = -5 + 2√5 and x = -5 - 2√5,
and their sum is (-5 - 2√5) + (-5 + 2√5) = -10.
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What is the sum of all values that satisfy the equation 3x2 + 30x + 15...
To find the sum of all values that satisfy the equation, we need to find the roots of the equation.
We can factor out a common factor of 3 from the equation:
3(x^2 + 10x + 5) = 0
Now, we have a quadratic equation in the form ax^2 + bx + c = 0, where a = 1, b = 10, and c = 5.
To solve this quadratic equation, we can use the quadratic formula:
x = (-b ± √(b^2 - 4ac)) / (2a)
Plugging in the values, we get:
x = (-10 ± √(10^2 - 4(1)(5))) / (2(1))
= (-10 ± √(100 - 20)) / 2
= (-10 ± √80) / 2
= (-10 ± 4√5) / 2
= -5 ± 2√5
The two solutions are -5 + 2√5 and -5 - 2√5.
The sum of these two values is (-5 + 2√5) + (-5 - 2√5) = -10.
Therefore, the sum of all values that satisfy the equation is -10.
Answer: a) -10