Try and get the variable by its self by -81 from both sides then divide it by 7 and get ur answer.
For this we almost have the following equation:

We must match the equation to zero:

From here, we clear the value of t.
We have then:

We discard the negative root because we are looking for time:
Answer:
it will take him to reach the ground about:

seconds
Answer:
4,9
Step-by-step explanation:
(1). 4,9 are not prime number
(2) 4=1×2×2
9 = 1×3×3
so,
HCF of 4,9 will be
= 1.
Answer:
the first step is correct
Step-by-step explanation:
the first step is correct
then draw 2 circles with the same radius with centre D and E ( the point BC intersect the first circle )
Where the 2 circles are intersecting is the point F
Then BF is the bisector