The discriminant is the value that is b^2 - 4ac.
When this number is <0 there will be 2 complex solutions. Letter D.
You would be taking the sqrt of a negative number resulting in a
" +- i sqrt of a number"
If Andrew were to rest, he would not be moving (walking). During such a period, the beginning distance would be the same as the ending distance.
In this graph there are two such time intervals: BC and DE. Notice how the graph is 'flat' on each; this 'flat' graph indicates a speed of zero.
The digit in the hundred millions place is 9.
Option C
For each value of y, -2 is a solution of -21 = 6y - 9
<u>Solution:</u>
Given, equation is – 21 = 6y – 9
We have to find that whether given set of options can satisfy the above equation or not
Now, let us check one by one option
<em><u>Option A) </u></em>
Given option is -5
Let us substitute -5 in given equation
- 21 = 6(-5) – 9
- 21 = -30 – 9
- 21 = - 39
L.H.S ≠ R.H.S ⇒ not a solution
<em><u>Option B)</u></em>
Given option is 3
- 21 = 6(3) – 9
- 21 = 18 – 9
- 21 = 9
L.H.S ≠ R.H.S ⇒ not a solution
<em><u>Option C)</u></em>
Given option is -2
- 21 = 6(-2) – 9
- 21 = - 12 – 9
- 21 = - 21
L.H.S = R.H.S ⇒ yes a solution
<em><u>Option D)</u></em>
- 21 = 6(9) – 9
- 21 = 54 – 9
- 21 = 45
L.H.S ≠ R.H.S ⇒ not a solution
Hence, the solution for the given equation is – 2, so option c is correct
