Answer:
-7x-56
Step-by-step explanation:
Answer:
300 girls were there in the gym.
Step-by-step explanation:
Given:
The ratio of the number of boys to the number of girls was 4:3, after 160 boys left the gym, the ratio became 4:5.
Now, to find the number of girls in the gym.
The girls in the gym does not left, their quantity is same before and after.
So, we multiply the both ratios to make the girls ratio same:
4:3 × 5 = 20:15
4:5 × 3 = 12:15
Now, <em>we find the units of the ratio</em>.
<em>The ratio of boys dropped down by 160</em>:
20 - 12 = 8 units.
160 = 8 units
Now, dividing both sides by 8 we get:
20 = 1 unit
So, 1 unit = 20.
Now, girls = 15 units
So, 15 × 20 = 300.
Therefore, 300 girls were there in the gym.
Answer:
-790
Step-by-step explanation:
Answer:
x= -2
Step-by-step explanation:
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!
