We can use the slope formula:
By plugging the values into this formula, we can solve for the slope.
-1 - 4 / -8 - 0
-5 / -8
Because there are two negatives, they cancel out;
The slope is 5/8
Option A
is one way to determine the factors of 
by grouping
<em><u>Solution:</u></em>
Factoring by grouping means that you will group terms with common factors before factoring
<em><u>Given expression is:</u></em>
Group the first two terms together and then the last two terms together.
We can see that 
is common in first two terms
And 3 is common in last two terms
Factor them out
Thus option A is correct
Remark
This is quite a nice little problem. It takes a minute or three to figure out the answer, and when you do, you will be certain that you have been tricked. It is a little like the egg of Columbus.
Solution
The Base of Triangle ABN is AB
The Base of Triangle CDM is CD
The height of both given triangles is h. That is the distance between the two parallel lines.
Area ABN = 1/2*AB * h = 23 cm^2
Area CDM = 1/2*CD * h = 18 cm^2
Now the Area of the trapezoid is
Area_Trapezoid = 1/2 * h (AB + CD) Using the distributive property Remove the brackets.
Area_Trapezoid = 1/2*AB*h + 1/2*CD*h Did you notice something? Those terms are just the area of the triangles (written above.)
Area Trapezoid = 23 + 18 = 41 cm^2 <<<< Answer
the answer this question is h=20 ft
