Abakery sold apple pies for $11 and blueberry pies for $13 one saturday they sold a total of 38 pies and collected a total of $460. how many pies did they sell and how many blueberry pies did they sell?

X=apple pies
y=blueberry pies

x+y=38
11x+13y=460
first you rearrange the first equation to become: y=38-x and then by using the substitution method you can do:

11x+13(38-x)=460
11x+494-13x=460
(combine like terms)
-2x+494=460
(-494 on both sides)
-2x=-34
(divide by -2 on both sides)
x=17

finally, you plug 17 in place for x in the first equation (original):

(17)+y=38
(-17 on both sides)
y=21
meaning they sold 21 blueberry pies!