Answer:
x=1/2
Step-by-step explanation:
Set up the equation: 2x-1=0
Add one to both sides. 2x=1
Divide two by both sides: x=1/2
Therefore, x =1/2, or .5
-7d > 21
d < -3
Remember the sign flips when you multiply or divide by a negative number.
You haven't provided the required roots, but I can tell you how to do this kind of exercises in general.
If the
coefficient is 1, i.e. the equation is written like
, then you can say the following about the coefficients b and c:
is the opposite of the sum of the roots
is the multiplication of the roots.
So, for example, if we want an equation whose roots are 4 and -2, we have:
So, the equation is 
If your roots are rational, you can work like this: suppose you want an equation with roots 3/4 and 1/2. You have:
And so the equation is

In order to have integer coefficients, you can multiply both sides of the equation by 8:
