Answer:
x = -3, 
Step-by-step explanation:
The given quadratic equation is: 
This can be written as: 
To solve a quadratic equation of the form
we use the formula:

Here, a = 2; b = 3; c = - 9
Therefore, the roots of the equation are:



We get two values of 'x', viz.,
x =
and 

⇒ x = -3, 3/2
Since the factors of the quadratic equation is asked, we write it as:
(x + 3)(x -
) = 0
because, if (x - a)(x - b) are the factors of a quadratic equation, then 'a' and 'b' are its roots.
Multiply (x + 3) and (x -
to see that this indeed is the given quadratic equation.
The ages are consecutive even numbers.
The youngest child is (x+3) years old.
Every even number is 2 more than the one before it.
So the three ages are
(x + 3), (x + 5), and (x + 7).
Their sum is x+3 + x+5 + x+7 = 3x + 15
But we're told that their sum is 42, so we can write
3x + 15 = 42 <== the equation
Subtract 15 from each side: 3x = 27
Divide each side by 3 : x = 9 <== the solution
So the three ages are 12, 14, and 16.
The oldest child is 16 years old.
Answer:
B
Step-by-step explanation:
(+)x(-)=(-)
(-)x(-)=(+)
Answer:
Table B
Step-by-step explanation: