Question 414225
1 The deli charges $3.80 for a breakfast of 3 eggs & 4 bacon strips. The charge is $2.75 for 2 eggs & 3 bacon strips. Find the cost of each egg and the cost of each bacon strip?
(Please help me I don't even no where to begin with these I freeze up.)

let egg = $x
bacon = $y
3x+4y=3.80...............1
2x+3y=2.75...............2

3	x	+	4	y	=	3.8	.............1	
2	x	+	3	y	=	2.75	.............2	
								
multiply (1)by -2			
Multiply (2) by 3			
-6x-2y	=-7.6		
6x+3y=8.25		
								
Add the two equations								
								
y=0.65		
								
Plug value of y in 							
3	x	+	4	y	=	3.8		
3	x	+	2.6		=	3.8		
3	x	+			=	1.2		
/	3							
x=	0.4							

eggs 40 cents, bacon 65 cents

#2 If 3/4 is added to three times a number, the result is 1/2 subtracted from twice the number. Find the number?
Let x be the number

3x+3/4 =2x - 1/2
3x-2x=-1/2 -3/4
x=-5/4


#3 Carol spent $32.25 to take her daughter's birthday party guest to the movies. Adult tickets cost $5.75 and children tickets cost  $3.00. If 8 people were at the party.how many of each ticket were bought?

adults x
children y

x+y =8..............1
5.75x+3y= 32.25.....2

1	x	+	1	y	=	8	.............1	
5.75	x	+	3	y	=	32.25	.............2	
								
multiply (1)by 					-3			
Multiply (2) by					1			
-3x-3y	=-24		
5.75x+3y	=32.25		
								
Add the two equations								
								
2.75x=8.25		
								
/2.75							
								
x=3						
								
plug value of x in (1)								
								
1x+1y=8		
3+1y=8		
y=8-3
y=5		
	

#4 A chemist working on a new project needs 12 liters of a 50% acid solution. The stockroom only has 40% and  70% solutions. How much of each solution should be mixed together to form 12 liters of a 50% solution?

percent	----------------	quantity
40	----------------	x
70	----------------	12-x
50.00%	----------------	12

40x+70(12-x)=50*	12
40x+840	-70x=600		
40x-70x	=600-840		
-30x=-240							
/-30											
x=8liters 40%							
									# 5 Solve: 2x-(3x-2)+5=17
2x-3x+2+5=17
-x+7=17
-x=10
x=-10