5 girls : 4 boys
5 + 4 = 9 students
= 27 students ( 5girls / 9 students )
*cancel students units*
= 27 ( 5 girls / 9)
= 15 girls
OK. I did it, and I have the solution.
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The length of the deck is (5 + 2x) .
The width of the deck is (4 + 2x) .
If the deck didn't have that big hole in the middle where the pool is,
then its area would be
(5 + 2x) · (4 + 2x) .
When you multiply that all out, you get Area = 4x² + 18x + 20
and the question tells us that the area of the whole big rectangle is 90 yds² .
So we can write
4x² + 18x + 20 = 90 .
Subtract 90 from each side: 4x² + 18x - 70 = 0
Divide each side by 2 : 2x² + 9x - 35 = 0
You can use the quadratic equation to solve that and find out that
x = 2.5 yards, and that's what the question is asking you.
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That makes the deck 10 yds high and 9 yds wide.
Total area of the whole big rectangle, (deck + pool ), = 90 yds².
Answer:
f(9)= -72
g(-9)= 225
Step-by-step explanation:
First put the original equation
f(x)=-7x-9
Next plug in the number f(9)
f(9)=-7(9)-9
After multiply -7(9) which gets you -63
f(9)=-63-9
Then subtract -63-9 which gets you -72
f(9)=-72
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First put the original
g(x)=6x3-23x
Next plug in the number g(-9)
g(-9)=6x3-23(-9)
After multiply 6x3 which gives you 18 then multiply -23(-9)
g(-9)=18+207
then add 18+207 which gives you 225
g(-9)=225
