According to Vieta's Formulas, if

are solutions of a given quadratic equation:
Then:
is the completely factored form of

.
If choose

, then:

So, according to Vieta's formula, we can get:

But

:
Answer:
Step-by-step explanation:
2nd one
Answer:
10x
Step-by-step explanation:
1.
In line with the test each person who came into interaction
with the infected person will become infected also. With this information, the
calculation would be: 9 people each day for 7days would be equivalent to 9 x 7
which equals 63 people.
2.
Here were 7 other people in the experiment if patient
zero is left out. If each person intermingled with 6 different people every day
in 7 days then the calculation would be: 7 people infected x 6 new people = 42
infected people each day
42 new people every day x 7 days = 294
infected persons.
If you would like to know which of the following steps should be performed to eliminate variable d first, you can find this using the following steps:
equation a: 2c = d - 8 /*(-3)
equation b: c = 3d + 8
__________________
-6c = -3d + 24
c = 3d + 8
__________________
-6c + c = -3d + 24 + 3d + 8
-5c = 32
5c = -32
c = -32/5
<span>The correct result would </span>be: <span>multiply equation a by −3.</span>