7+x, because the sum means adding.
Answer:
Step-by-step explanation:
-2x²-3x+8=0
disc.=b²-4ac=(-3)²-4(-2)(8)=9+64=73>0
it has two real irrational solutions.
This is a linear equation or y=mx+c. Where y is the number of mosquitos at a particular month and x is the number of months. We know the initial population of the mosquitoes is c=20. They population doubles every month so this is the gradient, m=2. Therefore the equation for the growth of the mosquito population is:
y = 2x + 20.
So after x= 10 months the mosquito population will be,
y=2(10)+20= 40.
There will be 40 mosquitoes after ten months.
900,000=10*90,000
So there are 90,000 tens in 900,000.
