It depends on what you are trying to calculate but the most common way I go to find percentage is to multiply by the number in decimal for ie. 50% = .5.
If you are looking for a way to do it quickly in your head I always take find out what 10% is like in the case of 100 it would be 10 so if I want to find 15% I know I can find 10% and if I cut what 10% is in half I will find 5% so likewise if I add what 10%+5% I will end up with 15%. For example, 10% of 100 is 10 half of 10 is 5 and 10+5 equals 15. If you need to find something like 20% or 30% I know that I can find 10% and instead of dividing(cutting it in half) I can multiply by 2 or 3. 10% + 10% =20%
I hope it helps, if you have more questions let me know!
If, for example, you had x on one side and x on the other, then subtracting x from both sides "disappears" x. If no other power of x shows up on either side, then your equation either has no solution or is always true.
Answer:
(-4,-3)
Step-by-step explanation:
The x value is -4 and the y value is -3
Answer:
C)x = +/-15
Step-by-step explanation:
15x15=225
-15x-15=225