Answer:
x=3, y=-1
Step-by-step explanation:
We are already given an equation solved for x, making substitution much easier. We know x=4y+7, meaning we can put 4y+7 whenever we see x in the second equation
2x-6y=12
We substitute 4y+7 in place of x
2(4y+7)-6y=12
Now we only have one variable to work on, distribute the 2
8y+14-6y=12
Combine similar terms, 8y-6y=2y
2y+14=12
Subtract 14 from both sides
2y=-2
y=-1
Now we plug in -1 for y in the first equation to find x
x=4(-1)+7
x=-4+7
x=3
$33.33
20/9 = $2.22 per sheet
$2.22*15 = $33.33
There are a total of 33 students in the class (21+12=33). There are 12 boys in the class so the chance of drawing a boys name would be 12/33 which reduces to 4/11. This means you will draw a boys name 4 times for every 11 draws. To find the percent probability, just divide...
4/11 =.3636
multiply by 100 to convert to a percentage ( move decimal to the right 2 places).
.3636 = 36.36%
There is a 36.36% chance that a boys name is drawn.
