Answer:
see explanation
Step-by-step explanation:
the sum to n terms of an arithmetic sequence is
=
[2a + (n - 1)d ]
where d is the common difference and a is the first term
here d = 9 - 7 = 7 - 5 = 2 and a = 5, hence
=
[(2 × 5) + 2(n - 1) ]
=
(10 + 2n - 2)
=
(2n + 8)
= n² + 4n
When sum = 165, then
n² + 4n = 165 ← rearrange into standard form
n² + 4n - 165 = 0 ← in standard form
(n + 15)(n - 11) = 0 ← in factored form
equate each factor to zero and solve for n
n + 15 = 0 ⇒ n = - 15
n - 11 = 0 ⇒ n = 11
but n > 0 ⇒ n = 11
Answer: The answer is y=-3x
Step-by-step explanation: You can see in the picture that the line is going down which represents a negative slope so you can eliminate C and D. Now you are left with A and B. 1 unit up is equal to 3 so the rise over run is -3/1 and that translates to Y=-3x answer B
Answer:
b.) 104
Step-by-step explanation:
Percent formula:
x/y = p/100
where x is the fraction, y is the total, and p is the percent
This means:
x = number of games the team won
y = total number of games
p = percent the number of teams won
Let's plug these values into the equation:
x/y = p/100
x/160 = 65/100
Solve by cross-multiplying:
x/160 = 65/100
100(x) = 100x
160(65) = 10,400
100x = 10,400
/100 /100
x = 104
Therefore, the team won 104 games.
Let Daniel's age be 'x' years , hence, Lisa's age is (x - 5) years. Let Grandma's age be 'y' = 54 years.
Hence,
x(x - 5) = 2/3 × y
x² - 5x = 2 × 54 years / 3
x² - 5x = 36 years
x² - 5x - 36 = 0
∆ = (-5)² - 4(1)(-36) = 25 + 144 = 169
√∆ = √169 = 13

x1 = (5+13)/2, x2 = (5-13)/2
x1 = 9, x2 = -4
Since, age can't be negative,
Daniel's age = x = 9 years.