Answer:
3.5×10^4=35000
Step-by-step explanation:
Consider the value
3.5
we are saying that we are counting in units (1's) in that we have
3
1
2
of 1's
'.....................................................................................
Consider the value
3.5
×
10
. Now we are saying we have
3
1
2
of tens. That is; 3 lots of 10 is 30 and
1
2
of 10 is 5 so we have
30
+
5
=
35
'.................................................................................
Note that
10
2
is 100
Consider the value
3.5
×
10
2
. Now we are saying we have
3
1
2
of
100
'
s
So if we are counting in 100's then the decimal point stays where
it is and we move the number of 3.5 to the left until the
3 becomes hundreds.
Note that we have to insert a place holder of 0 just to the left of the decimal point to make sure the three is viewed as in the hundreds.
3.5
×
10
2
−−−−−−−−−−−−−−−−−−→
slide to the left 2 places
350.0
36
Step-by-step explanation:
5x is 15
x is 3
12 times 3 is 36
d = 3 , a₁₂ = 40 and S
= 7775
In an arithmetic sequence the nth term and sum to n terms are
<h3>• a
= a₁ + (n-1)d</h3><h3>• S
=
[2a + (n-1)d]</h3><h3>
where d is the common difference</h3><h3>a₆ = a₁ + 5d = 22 ⇒ 7 + 5d = 22 ⇒ 5d = 15 ⇔ d = 3</h3><h3>a₁₂ = 7 + 11d = 7 +( 11× 3) = 7 + 33 = 40</h3><h3>S₁₀₀ =
[(2×7) +(99×3)</h3><h3> = 25(14 + 297) = 25(311)= 7775</h3>
2 1/2 for $6.25 is the answer
22.5/(x-6) + 22.5/(x+6) = 9
multiply by x-6
=> (x-6)22.5/(x-6) + (x-6)22.5/(x+6) = 9(x-6)
=> 22.5 + (x-6)22.5/(x+6) = 9(x-6)
multiply by x+6
=> (x+6)22.5 + (x+6)(x-6)22.5/(x+6) = 9(x-6)(x+6)
=> (x+6)22.5 + (x-6)22.5 = 9(x-6)(x+6)
distribute
=> 22.5x+6(22.5) + 22.5x - 6(22.5) = 9(x^2 - 36)
=> 45x = 9x^2 - 9(36)
=> 0 = 9x^2 - 45x - 9(36)
divide by 9
=> 0 = x^2 - 5x - 36
=> 0 = x^2 - 5x - 36
=> 0 = (x - 9)(x + 4)
x=9 and -4
