Answer:
Given equation have two solutions.
x =
Right option is (D)
Step-by-step explanation:
We have given,
we can rewrite this equation in the form given as:
6x² + 40 + 31x = 0
or 6x² + 31x + 40 = 0
On solving this quadratic equation, we get :
x =
That means, given equation have two solutions.
Right option is (D)
Answer:
r=
Step-by-step explanation:
The sum to infinity of a geometric series is calculated as
S∞ = ; | r | < 1
where a₁ is the first term and r the common ratio
here a₁ = 15 and S∞ = 45 , then
45 = ( multiply both sides by (1 - r ) )
45(1 - r) = 15 ( divide both sides by 45 )
1 - r = =
( subtract 1 from both sides )
- r = - 1 = -
( multiply both sides by - 1 )
r =
