Answer:
x = -2; y = 3
Step-by-step explanation:
5x + 4y = 2 (1)
3x + 3y = 3 (2)
Multiply (1) by 3 and (2) by 4
15x + 12y = 6 (3)
12x + 12y = 12 (4)
Subtract (4) from (3)
15x - 12x = 6 - 12
3x = -6
x = -6/3
x = -2
Substitute x = -2 into (1)
5x + 4y = 2
5(-2) + 4y = 2
-10 + 4y = 2
4y = 2 +10
4y = 12
y = 12/4
y = 3
The first error is when he multiplied equation (2) by 4
He didn't multiply the right hand side of the equation by 4
3x + 3y = 3 ×4
12x + 12y = 12
But he wrote
12x + 12y = 3
The the next error is subtracting the left hand side of the equation and adding the right hand side
15x + 12y = 6
12x + 12y = 3
He wrote
3x = 9
Instead of 3x = 3
=21x + 35y + 4y
= 21x + 39y
Answer:
D. $53,650
Hope this helps, sorry if it's wrong :)
Answer:
i think they are
Step-by-step explanation:
Correct question:
Every day Kim practice volleyball and clarinet each day she practices volleyball for 2.5 hours if after 8 days she practices both volleyball and the clarinet for a total of 36 hours how many hours per day did Kim practice clarinet.
Answer: 2 hours
Step-by-step explanation:
Everyday Kim practices volleyball and clarinet = v/ball + clarinet
Everyday volleyball practice = 2.5hours
That is clarinet(hours) + 2.5 hours of volleyball
After 8 day, total practice hours of both volleyball and clarinet equals 36 hours
The above information can be represented mathematically as thus:
Let h = hours per day of clarinet
8(h + 2.5) = 36
8h + 20 = 36
8h = 36 - 20
8h = 16
h = 16/8
h = 2