Question
The booster club is selling refreshments. The following system of linear equations models the concession stand prices. Let represent the cost of a hot dog and represent the cost of the soda. Write the answers in decimal form. Solve the system of linear equations.
4h+4s=10
7h+5s=15
4h+4s=10
7h+5s=15
Answers
GPT 3.5
To solve the system of linear equations, we need to use the substitution or elimination method. Let's use the elimination method in this case.
Multiply the first equation by 5 and the second equation by -4 to make the coefficients of either h or s the same but with opposite signs:
First equation:
5(4h + 4s) = 5(10)
20h + 20s = 50
Second equation:
-4(7h + 5s) = -4(15)
-28h - 20s = -60
Now, we add the two equations to eliminate variable s:
20h + 20s = 50
-28h - 20s = -60
_________________
-8h = -10
Divide both sides by -8:
h = -10/-8
h = 1.25
Now, substitute the value of h back into the first equation to solve for s:
4(1.25) + 4s = 10
5 + 4s = 10
4s = 5
s = 5/4
s = 1.25
Therefore, the cost of a hot dog is $1.25 and the cost of a soda is $1.25.
Multiply the first equation by 5 and the second equation by -4 to make the coefficients of either h or s the same but with opposite signs:
First equation:
5(4h + 4s) = 5(10)
20h + 20s = 50
Second equation:
-4(7h + 5s) = -4(15)
-28h - 20s = -60
Now, we add the two equations to eliminate variable s:
20h + 20s = 50
-28h - 20s = -60
_________________
-8h = -10
Divide both sides by -8:
h = -10/-8
h = 1.25
Now, substitute the value of h back into the first equation to solve for s:
4(1.25) + 4s = 10
5 + 4s = 10
4s = 5
s = 5/4
s = 1.25
Therefore, the cost of a hot dog is $1.25 and the cost of a soda is $1.25.