The number of different groups can be found by finding 9C3 (Using combinations)
We will find combinations from n = 9 to r = 3
Therefore, 9C3 = 9!/6!*3! = (9*8*7*6!)/(6!*3*2)
= 3*4*7
= 84 ways.
Answer:

Step-by-step explanation:
You can solve this two ways: insert the values into point-slope form and simplify to solve for y, converting it to slope-intercept form, <em>or</em><em> </em>insert the values into slope-intercept form, solve for b, and insert b. We'll do both :)
<em><u>Point-slope form:</u></em>

Where:
is the slope
and
are corresponding coordinate points 
Insert the given values:

Solve for y. Expand the right sie using the distributive property:

Isolate the variable. Subtract 6 from both sides, canceling out the 6 on the left:

<em>OR</em>
<em></em>
<em><u>Slope-intercept form:</u></em>

Where:
is the slope
is the y-intercept
and
are corresponding coordinate points 
Insert the given values:

Simplify the multiplication:

Solve for b. Add 10 to both sides, canceling out the 10 on the right:

The value of b is 4. Insert the appropriate information into the equation. When using slope-intercept form, you don't plug in the coordinate points:

:Done
Answer:
4.5 x 30 = 135
0.1 x 30 = 3
Hint: something multiplied by 0.1 is the same as that same thing divided by 10.
Answer:
-1
Step-by-step explanation:
If i = √-1, then i^2 = -1.