I believe that x=9. I used cross multiplication. First, I multiplied 6 by 15. Second, I divided this product of 90 by 10. The quotient is 9.
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
He played 5% if im correct