Answer:
D=1/2
Step-by-step explanation:
Multiply the numbers
Subtract the numbers
Combine like terms
put 1/2 to the two parts of the equation
last but not least, simplify
Answer:
Step-by-step explanation:
A 2nd order polynomial such as this one will have 2 roots; a 3rd order polynomial 3 roots, and so on.
The quadratic formula is one of the faster ways (in this situation, at least) in which to find the roots. From 2x^2 + 4x + 7 we get a = 2, b = 4 and c = 7.
Then the discriminant is b^2 - 4ac, or, here, 4^2 - 4(2)(7), or -40. Because the discriminant is negative, we know that the roots will be complex and unequal.
Using the quadratic formula:
-4 ±√[-40] -4 ± 2i√10
x = ------------------ = ------------------
4 4
-2 ± i√10
Thus, the roots are x = ------------------
2
Deductive thinking: When you start with a given set of rules and conditions and determine what must be true as a consequence.
So the answer is true.
Step-by-step explanation:
y=6+4x, as equation (iii)
=> -5x-(6+4x)=21
=> -5x-6-4x=21
=> -5x-4x-6=21
=> -9x-6=21
=> -9x=21+6
=> -9x=27
x= -3, by dividing both sides by -9
So, by inserting x in the first equation,
=> -4(-3)+y=6
=> 12+y=6
=> y=6-12
=> y= -6.
Therefore, x= -3 and y= -6
77/5=99/x
77x=5*99
77x=495
x=495/77
x=6.4
she needs to study 6.4 hrs to get 99