To show: (x+y)² − (x −y)² = 4xy
Using difference of square identity:
Taking left side






hence proved

Answer:
it can not be made into a regular fraction. but it can be made into a whole number. the whole number would be 710
Step-by-step explanation:
So if she got them at 30% off that means
$63 = 70%
divide both sides by 70 to get 1%
$0.90 = 1%
multiply by 100 to get full price
$90 = 100%
original price was $90