Answer:

Step-by-step explanation:

So 400,000 DVD sales with a 31% decline means in the 1st year following, there will be a decline of 124,000 DVDs sold. So we need to take 400,000 - 124,000, which equals a starting point for year two is 276,000 DVDs.
So a 31% decline on 276,000 = 85,560. So we need to subtract that from 85,560 from 276,000 which is 190,440. So at the end of the second year, DVD sales were only 190,440. That's also out starting point of the 3rd year.
So 31% of 190,440 equals 59,036.4 for the third year of DVD sales. So we need to subtract 59,036.4 from out third year starting point of 190,440, which equals 131,403.6, but since you can't have parts of DVDs, we'll round the decimal point fraction to a whole number to end up with 131,404 DVDs sold in year three.
So after three years of a 31% yearly decline in DVD sales you end up with DVD sales are 131,404
Let the number sold of veggie pizza be a
The number sold of cheese pizza be b
a+b=25…1
A+7=b…2
Sub 2 into 1
a + a+7 = 25
2a+7=25
2a=18
a=9
Sub a=9 into 2
9+7=b
b=16
They sold 9 veggie pizza and 16 cheese pizza
Im not sure why it brought me here it just brought me here sorry