Answer:
$[tex]$2.25[/tex]
Step-by-step explanation:
Let [tex]b =[/tex] the cost of one brownie, [tex]c =[/tex] cost of one cookie
[tex]3b + 5c = 11[/tex]
[tex]b+2c = 3.95[/tex]
Times [tex]3[/tex] on both sides on the second equation above to get the following:
[tex]3b + 6c = 11.85[/tex]
[tex]3b+6c - (3b+5c) = 11.85-11[/tex]
[tex]3b+6c-3b-5c = 0.85[/tex]
[tex]c = 0.85[/tex]
To find the value of [tex]b[/tex], use substitution:
[tex]b+2c = 3.95[/tex]
[tex]b = 3.95-2c[/tex]
[tex]= 3.95 - 2\times0.85[/tex]
[tex]= 2.25[/tex]
[tex]\therefore[/tex] the cost of a brownie is $[tex]$2.25[/tex]
Hope this helps :)