Answer:
x=4, y=-4/3. (4, -4/3).
Step-by-step explanation:
8x+9y=20
x=-3y
---------------
8(-3y)+9y=20
-24y+9y=20
-15y=20
y=20/-15
simplify
y=-4/3
x=-3(-4/3)=12/3=4
Answer:
840
Step-by-step explanation:
There is a common difference d between consecutive terms, that is
d = 14 - 7 = 21 - 14 = 7
This indicates the sequence is arithmetic with n th term
= a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Here a₁ = 7 and d = 7 , thus
= 7 + (119 × 7 ) = 7 + 833 = 840
Recall that

There are three cases to consider:
(1) When

, we have

and

, so

(2) When

and

, we get

and

, so

(3) When

, we have

and

, so

So