Boys: x
gilrs: y
From the text of the task:

Replacing x:

So there are 28 girs and 20 boys
$4.30
Do ten times $3.57 and subtract it from $40
Answer:
x=-2
Step-by-step explanation:
6(x + 1) = -2(3x + 9)
Distribute 6 and -2.
6x+6=-6x-18
Move the variable to the left-hand side and move the constant to the right and change their signs.
6x+6x=-18-6
Collect like terms.
12x=-24
Divide both sides of the equation by 12.
x=-2
Hope this helps :)
Answer:
Step-by-step explanation:
a. 3-4x=-7-4x
3=-7. no solution
b. 15 - 2x = -7x
15 = -5x
x=-3. one solution
c. 7y-21=6y-21
y=0
1. -3x+4=-3x+7
4=7
2. 10+2x = 5x+2
8=3x
x=3/8
3. x+5=x+5