Question 800832
Rita has 21 coins which are all dimes and quarters. If the value of the quarters is 35 cents more than the value of the dimes, how many dimes does Rita have? Please answer as soon as possible

dimes =x
quarters = y
x+y=21.....................(1)

10x+35=25y
10x-25y=-35
/5
2x-5y=-7.................(2)


1	x	+	1	y	=	21	.............1	
Total value								
2	x		-5	y	=	-7	.............2	
Eliminate	y							
multiply (1)by		5						
Multiply (2) by		1						
5	x		5	y	=	105		
2	x		-5	y	=	-7		
Add the two equations								
7	x				=	98		
/	7							
x	=	14						
plug value of			x	in (1)				
1	x	+	1	y	=	21		
14		+		y	=	21		
				y	=	21		-14
				y	=	7		
				y	=	7		
x=	14		Number of	dimes				
y=	7		Number of	quarters				
m.ananth@hotmail.ca