Answer: x+2 / x+ 9, x = -2, x=-9 ( A )
Solution:
Breakdown the problem into two sets
Step 1: simplify x^2 -10x - 24
Factorize the above equation,
Multiply the last term (24) with the first term coefficient i.e. 1
Step 2: Then, find the factors of 24 in a way that when you add or subtract it sums up to 10
x2 - 12x + 2x - 24 >>>> (x2-12x) + (2x-24) >>> take common
>>>> x(x-12) + 2( x-12)
Step 3: (x + 2) (x - 12)
Step 4: Step 1: simplify x^2 - 3x - 108 using the same steps
x2 - 12x + 9x - 108 >>>> take common x(x-12) + 9 ( x -12) >>>
(x + 9) (x - 12) final product
Now, Simplify the equation as a whole
(x + 2) (x - 12) / (x + 9) (x - 12) Note: (x - 12) cancels out
= (x + 2) / (x + 9) with x= -2 and x= -9
The rule of scientifinc notation is that we can use number between 0 and 10, so here we can use 2.8. Lets do this
280 000 000 = 2.8 * 100 * 1 000 000
Now we can just multiply 2.8 by 10 to the power of number of 0 reapeted
So
- its the result
Answer:
Explanation:
1. x represent the copybook while y represent the pen that is bought.
2. 2x + 3y = 9000 means that in order to buy 2 copybooks and 3 pen you have to pay 9000 LL.
3. Solve for the price of x and y
2x + 3y = 9000 (1)
4x + 2y = 8000 (2)
Multiply (1) by -2:
-2(2x + 3y = 9000)
4x + 2y = 8000
——————————
-4x - 6y = -18000
4x + 2y = 8000
—————————
-4y = -10000
y = -10000/-4
y = 2500
Substitute y value into (2):
4x + 2(2500) = 8000
4x + 5000 = 8000
4x = 3000
x = 3000/4
x = 750
Therefore, 1 copy book = 750LL and 1 pen = 2500 LL
4/10 would be 2/5 in simplest form.
I hope this helps! (:
