Answer:
19.
log9(5x^2 + 10) - log9(10) = 1
<=> log9((5x^2 + 10)/10) = log9(9)
<=> (5x^2 + 10)/10 = 9
<=> 5x^2 + 10 = 90
<=> 5x^2 = 80
<=> x^2 = 16
<=> x = +/- (4)
20.
log5(2x^2 + 4) + log5(3) = 2
<=> log5((2x^2 + 4) x 3) = log3(9)
<=> 6x^2 + 12 = 9
<=> 6x^2 = -3
=> No real x satisfies. ( x^2 always larger or equal to 0)
21.
log6(8) + log6(7 - 2x^2) = 2
<=> log6(8 x (7 - 2x^2)) = log6(36)
<=> 56 - 16x^2 = 36
<=> 16x^2 = 20
<=> x^2 = 5/4
<=> x = +/- sqrt(5/4)
Hope this helps!
:)
Answer:
You can get it by doing this
Step-by-step explanation:
The Probability
Answer:
7.5^2
56.25
Step-by-step explanation:
Answer:
Anita's monthly bill will be $164.25.
Step-by-step explanation:
Since Anita has a cellphone contract that costs her R100 per month plus 85 cents per peak time SMS, and 25 cents per off-peak time SMS, if she sends 45 SMSs during peak time and 105 SMSs during off-peak time In a month To determine what will her monthly bill come to, the following calculation must be performed:
100 + (0.85 x 45) + (0.25 x 105) = X
100 + 38.25 + 26.25 = X
138.25 + 26.25 = X
164.25 = X
Therefore, her monthly bill will be $ 164.25.
4.72n - 0.1 = 8 + 0.67n
4.72n - 0.67n = 8 + 0.1
4.05n = 8.1
4.05n/4.05 = 8.1/4.05
n = 2
