Respuesta :
Answer:
Solutions: (2,10), (4,5)
Not solutions: (1,12), (6,10), (12,8), (18,6)
Step-by-step explanation:
Let x be the number of packages of pasta and y be the number of jars of pasta sauce. If pasta costs $1 for a 1-pound package, then x packages of pasta cost $x and weigh x pounds. If pasta sauce costs $3 for a 1.5 pound jar, then y jars cost $3y and weigh 1.5y pounds.
1. Tyler has $36, then
[tex]x+3y\le 36.[/tex]
2. Tyler can carry up to 20 pounds of food in his backpack, then
[tex]x+1.5y\le 20.[/tex]
You get the following system of inequalities:
[tex]\left\{\begin{array}{l}x+3y\le 36\\ x+1.5y\le 20\end{array}\right.[/tex]
Now substitute the coordinates of each point:
(1,12):
[tex]\left\{\begin{array}{l}1+3\cdot 12=37> 36\\ 1+1.5\cdot 12=19\le 20\end{array}\right.[/tex]
False, because first inequality doesn't hold.
(2,10):
[tex]\left\{\begin{array}{l}2+3\cdot 10=32\le 36\\ 2+1.5\cdot 10=17\le 20\end{array}\right.[/tex]
True, both inequalities hold.
(4,5):
[tex]\left\{\begin{array}{l}4+3\cdot 5=19\le 36\\ 4+1.5\cdot 5=11.5\le 20\end{array}\right.[/tex]
True, both inequalities hold.
(6,10):
[tex]\left\{\begin{array}{l}6+3\cdot 10=36\le 36\\ 6+1.5\cdot 10=21> 20\end{array}\right.[/tex]
False, because secondt inequality doesn't hold.
(12,8):
[tex]\left\{\begin{array}{l}12+3\cdot 8=36\le 36\\ 12+1.5\cdot 8=24> 20\end{array}\right.[/tex]
False, because second inequality doesn't hold.
(18,6):
[tex]\left\{\begin{array}{l}18+3\cdot 6=36\le 36\\ 18+1.5\cdot 6=27> 20\end{array}\right.[/tex]
False, because second inequality doesn't hold.