Answer:
see explanation
Step-by-step explanation:
The n th term of an arithmetic progression is
= a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Given
= 12 and
= 22, then
a₁ + 5d = 12 → (1)
a₁ + 7d = 22 → (2)
Subtract (1) from (2) term by term to eliminate a₁
2d = 10 ( divide both sides by 2 )
d = 5
Substitute d = 5 into (1) to find a₁
a₁ + 5(5) = 12
a₁ + 25 = 12 ( subtract 25 from both sides )
a₁ = - 13
Thus
= - 13 + 5 = - 8
= - 13 + 5(n - 1) = - 13 + 5n - 5 = 5n - 18 ← n th term
Answer:
A) Divide 20 by 2 and then add 8 to the result
Step-by-step explanation:

Answer: x^2 + 9x + 20
Step-by-step explanation:
Foil Method: (a + b) (c + d) = ac + ad + bc + bd
Lets say:
a = x
b = 5
c = x
d = 4
Plugging in the numbers: xx + 4x + 5x + 5*4
Combine like terms:
xx = x^2
4x + 5x = 9x
5 * 4 = 20
You're then left with: x^2 + 9x + 20
Answer:
y=10x
Step-by-step explanation: