C = 9/28 = 0.321
https://www.tiger-algebra.com/drill/3c-3/4=2c/3/
Answer:
CD = 27
Step-by-step explanation:
Given the triangles are similar then the ratios of corresponding sided are equal, that is
= 
, substitute values
= 
= 3 ( multiply both sides by 9 )
CD = 27
Answer: D ( 17/20)
Step-by-step explanation:
The two choices are:
The ‘standard’ tariff charges = $0.10 per unit
The ‘day/night tariff’ = $0.12 per unit for each unit consumed between 06:00 and 22:00 but only $0.05 for each unit consumed between 22:00 and 06:00
The day time is between 22:00 and 06:00
Time = 22 - 6 = 16 hours
Let assume that the charges are unit per hour.
For standard tariff = (16 × 0.10) + 0.2
Standard tariff = 1.6 + 0.2 = 1.8
For day/night = (16 × 0.12) + 0.2
= 1.92 + 0.2
= 2.12
The proportion will be
1.8/2.12 = 17/20 ( approximately)
Answer:
The third option (9+
--
)
Step-by-step explanation:
With FOIL, this can be expanded. (a+b)(a-b) is equal to a²+ab-ab-b² or a²-b².
In this case, all the answers have 4 terms, so we want the first option. This makes the equation 3²+(3×
)-(3×)-()².
Solving these gives 9+--7. This is the same as 9+--.
**This content involves multiplying with surds and expanding perfect squares, which you may wish to revise. I'm always happy to help!
