00:01
So i see that you need help with this question.
00:01
It says approximately 70 % of clear cutting, cutting down all or most trees in the area in a brazilian rainforest is to provide land for cattle ranchers and farming.
00:15
This accounts for 15 % of the world's total annual deforestation, making it the largest cause of deforestation worldwide.
00:24
The graph below represents the forest cover in the brazilian rainforest since 1970.
00:29
Determine the linear equation that represents the relationship between the amount of forest cover in the brazilian amazon and the year.
00:38
Allow x to be the number of years since 1970.
00:41
What does the y intercept represent? what does the gradient represent? so for a, the equation is y equals, and i start at 40 ,000 and then i stop here.
00:57
So that's one, two, three, one, two, three, four, five.
01:06
So 4 ,000 ,000 minus 3 ,800 ,000.
01:17
So that's 200 ,000 divided by five.
01:22
So that's 40 ,000.
01:24
So 40, 40.
01:29
Okay, so that's minus 40 ,000 x plus 4 ,000 ,000.
01:42
One, two, three, four, five.
01:45
Okay, so that makes sense.
01:47
And then the y intercept is the forest in 1970 started with 4 ,000 ,000 kilometers, oops, kilometers squared of rainforest, of forest cover.
02:32
Okay, and then the gradient, which is also known as the slope, decreasing 40 ,000 kilometers squared per year.
02:48
Assume that the deforestation rate is constant.
02:51
Calculate the approximate area of the forest that is cleared annually.
02:56
So that is the gradient.
02:59
So 40 ,000 kilometers squared per year is cleared.
03:14
C, to put this area in perspective, research an area in erbil in square kilometers.
03:20
How does it compare with the area of the forest that is cleared each year? so erbil is 1 ,431 ,580 kilometers squared, okay? oh, wait a minute, no, it's not, sorry.
03:49
It is 14 ,471 kilometers...