Answer:
A. X^2
Step-by-step explanation:
The best way to multiply complicated problems mentally* is to break them into chunks.
Start with 20 times 8 to get 160, and then 8 times 5 to get 40. Add these together to get 200. 200 times 3 is 600, and 20 times 200 is 4000. Add these together to get your final answer, 4600.
In other words 8 x 20 + 8 x 5 = 200 200 x 3 + 200 x 20 = 4600
*I assumed you meant mentally, because otherwise you'd just multiply longhand, multiplying two of the three numbers and then multiplying their product with the third.
Answer:
a=4 and b = 0
Step-by-step explanation:
Given : 
To find, The value of a and b
Solution,
Solving LHS of the given equation,

Since,

So,

or

On comparing we get :
a = 4 and b = 0
There would be 3 boxes of pink ribbon and 2 of yellow ones
Answer:
x=-5
Step-by-step explanation:
opening the bracket on the LHS, we have
-8x-40= -3x+x-7-3
-8x-40= -2x-10
collecting like terms
-8x+2x= -10+40
-6x= 30
divide both sides by -6
x= -5