Answer:
a = 3
Step-by-step explanation:
Since x = 7 is a solution, substitute x = 7 into the equation and solve for a
4(7) - 2(7 + a) = 8 , that is
28 - 2(7 + a) = 8 ( subtract 28 from both sides )
- 2(7 + a) = - 20 ( divide both sides by - 2 )
7 + a = 10 ( subtract 7 from both sides )
a = 3
Answer:
91
Step-by-step explanation:
Mean is calculated as
mean = 
let x be his test score of his last test , then
= 85 ( multiply both sides by 7 )
504 + x = 595 ( subtract 504 from both sides )
x = 91
Answer:
12 trades
Step-by-step explanation:
Let's call 'x' the number of trades they will do.
After each trade, the number of cards Ian has increase by 1 (he gives 1 but receives 2), and the number of cards Jason has decrease by 1 (he receives 1 but gives 2), so after x trades, the number of cards Ian has is 20 + x, and Jason has 44 - x.
To find the number of trades when they will have the same amount of cards, we have that:
20 + x = 44 - x
2x = 24
x = 12 trades
