7x+10=1/3×(12x-3)+14x
7x+10=1/3×3(4x-1)+14x
7x+10=(4x-1)+14x
7x+10=4x-1+14x
7x+10=18x-1
7x-18x=-1-10
-11x=-11
x=1
6x^4-17x^3-7x^2+13x=3
6x^4-17x^3-7x^2+13x-3=3-3
6x^4-17x^3-7x^2+13x-3=0
y=6x^4-17x^3-7x^2+13x-3
y=0
The solutions are: x=-1, 1/2, 1/3 and 3
Answer:
- after week 7: 4374 pennies
- 486 pennies: after week 5
Step-by-step explanation:
The sequence values have a first term of 6 and a common ratio of 3, so can be described by the formula ...
an = 6·3^(n-1)
This can be rearranged to ...
an = 2·3^n
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When n=7, the value is ...
a7 = 2·3^7 = 4374 . . . . pennies saved after 7 weeks
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To find when there are 486 pennies saved, we can solve the equation ...
486 = 2·3^n
243 = 3^n
log(243) = n·log(3) . . . . . . . take the logarithm
log(243)/log(3) = n = 5 . . . . divide by the coefficient of n
Tabitha will have saved 486 pennies after 5 weeks.
Hello!
That problem looks pretty messy... let's clean it up! :D
so we have this -----> -0.3(0.7x - 0.9) = -1.83 let's get simplifying
-0.21x + 0.27 = -1.83 -----> I distributed the -0.3 among 0.7x and -0.9
-0.21x = -2.1 -----> I subtracted 0.27 on both sides of the equation
<u>x = 10</u><u /> -----> I divided -0.21 on both sides of the equation
The answer you're looking for is D!
I hope this helps! :D
<u>Please vote me for Brainliest if there is a second answer!</u>