Let the youngest sister be n years
Lana will be 2n years, as her youngest sister is half her age
The age of the twins separately will be 2n-2 as they are 2 years younger than Lana
So, the equation looks like this:
n + 2n + 2(2n-2) = 45
Now solve for n:
3n + 4n - 4 = 45
7n - 4 = 45
7n = 49
n = 7
So the youngest sister is 7, Lana is 14 and the twins are 12. 14 + 12 + 12 + 7 =45
10.5x = 7.5x + 30
10.5x - 7.5x = 30
3x = 30
x = 30/3
x = 10
10.5(10) = 105
7.5(10) + 30 = 75 + 30 = 105
they need to purchase 10 t-shirts from each company for a total of $105 for each company
15, 4000, and <span>0, 10,000.
to find the slope, subtract the y values over the x values
10000-400/0-15
6000/-15
divide.
</span>6000/-15 = -400
the slope is -400. Hope this helps! :D
