First set up your two equations:
x + y = 90
x = 2y - 30
Then substitute what x equals in the second equation into the first equation:
(2y -30) + y = 90
Now solve for y:
3y -30 = 90
3y = 120
y = 40
Then use y = 40 and substitute the value for y into one of your original equations and solve for x. I'll choose the first one, but either one will work.
x+ 40 = 90
x = 50
So your solution is x = 50 and y = 40
Answer:
he can buy 2
Step-by-step explanation:
Answer:
42+18=6(7+3)
Step-by-step explanation:
6x7=42 and 6x3=18
You can see the polygon in the attached figure.
It's a trapezoid, so it's not equilateral, nor regular.
Answer:
p=ak^t
p1=491272*k^0
p2=782341*k^10
782341/491272 = k^10
k=1.047629
growth rate is 4.7629%
2012: predicted population is 491272*1.047629^12=858,642 people
1245863=491272*1.047629^t
1.047629^k=2.5363599
ln both sides is k ln 1.0476=ln 2.5363
t=20.000 years.
Rule of 72 would say 72/4.76 or 15.12 years for doubling
14.90 years
2017 predicted is 491272*1.0476^17 or 1083552, or more than actual, so the rate of growth is slowing down.
