You would think it was 3 * 12 = 36. Not so. All polygons have to be broken down into some figure that will give 2 dimensions that are at right angles to each other. That would mean that
d1 * d2 = Area for the small polygon
3d1 * 3d2 = area of the larger polygon
What that means is that the area of the larger one is 9 times the smaller one.
Area large = 12 * 9 = 108 square units. <<<<< answer.
If you find this hard to be leave try it with a square.
Suppose you have a square (the small one) that is 3 cm by 3 cm
The small one has an area of 3*3 cm^2 = 9 cm
Now you have another square that is 3 times larger. That means that each side is 3*3 = 9
So s = 9
Area = s^2
Area = 9^2 = 81 cm^2
81 is 9 times larger than 9 just as you would think.
Work it exactly like the other one with Wilda and Karla.
Juan takes 15 hours to do a job ... he does 1/15 of it in an hour.
His father can do it in 6 hours ... he does 1/6 of it in an hour.
Juan works alone for 4.5 hours. In that time, he does 4.5/15 = 0.3
of the job. When his father joins him, there's only 0.7 of it to finish.
Working together, they do (1/15 + 1/6) = (2/30 + 5/30) = 7/30 of the job
each hour.
How many times do they have to do 7/30 of the job in order to finish
the 7/10 of it that remains ? That will be the number of hours they need.
(7/10) / (7/30) = 7/10 x 30/7 = <em>3 hours</em>.
Then they can knock off while it's still daylight, and go for a swim.
The parabola has a minimum value of -3 due to the subtraction at the end of the equation.
