It does not say simple or compound interest.
Simple interest is rarely used these days, so assume compound.
Use the standard formula:
future value = present value*(1+rate/n)^(nt)
n=number of times interest is compounded per year (=1)
t=number of years
Plugging values,
200=100(1.09)^t
1.09^t = 2
take log
t(log(1.09))=log 2
t=log(2)/log(1.09)=0.6931/0.08618=8.04 years.
Step-by-step explanation:
8(b+1)=-3(2+b)
8b+8=-6-3b
8b +3b = -6-8
11b = -14
b = -14/11
(2x/-5x)+x^2
(x(2)/(x(-5))+x^2
(-2/5)+x^2, the x values cancel in numerator and denominator and simplify to -2/5
