Answer: There are 36 cows that can eaten 72 acres of grass in 126 days.
Step-by-step explanation:
Let x be the amount of grass in an acre initially.
Let y be the amount of grass grown in an acre per day.
Since we have given that
12 cows can eat 10 acres of grass in 28 days
12×28 = 10x + 10×28 y
336 = 10x + 280 y----------------------------(1)
Similarly,
21 cows can eat 30 acres of grass in 63 days.
21×63 = 30x + 30×63 y
1323 = 30x +1890 y ---------------------------(2)
So, by graphing method, we get the value of x and y

So, we have, 72 acres of grass in 126 days, we need to find the number of cows.
So, it becomes,
c×126 = 72x + 72×126 y

Hence, there are 36 cows that can eaten 72 acres of grass in 126 days.
(4,9) is on y=2+3x is equal to 9
Answer:
D.
Step-by-step explanation:
First, multiply straight across and put everything together:

Notice we can simplify by cancelling a b and reducing 3/12:

This cannot be simplified further.
D.
Answer:
ur light yagami u got this (right here I'd put eye roll emojis but thx to this app I cant)
Answer: The answer is true.
Step-by-step explanation: The given statement is :
" The area of a regular heptagon can be found by breaking the heptagon into seven congruent triangles and then taking the sum of their areas".
We are to check its is true or false.
In the attached figure, a regular heptagon ABCDEFG is drawn. Sine the heptagon is regular, so all its sides are equal and all its angles are also equal. So, we can break the heptagon into seven congruent triangles 1, 2, 3, 4, 5, 6 and 7 taking 'O' as the centre of the heptagon.
Finding the areas of these seven triangles and taking the sum will result in the area of the heptagon ABCDEFG.
Thus, the given statement is "TRUE".