The value of football is -21. The value of the helmet is -42. The value of the play chart is 60. The value of padding is 60. The value of the question mark is 165.
Let the football be x and the helmet be y. So, as per the first equation:
x+x=y
2x=y
Substituting this in equation 2 we get:
-3(2x+1)=123
-6x-3=123
-6x=123+3
-6x=126
x=126/-6
x=-21
Therefore, the value of football is -21.
Substituting the value of football in the first equation, we get:
-21-21=y
y=-42
Therefore, the value of the helmet is -42.
Now, let's consider the play chart to be (a) and padding to be (b). So, the third equation becomes:
a+b-(-21)=141 (as we calculated the value of football to be -21)
a+b+21=141
a+b=141-21
a+b=120
Now, adding the equations three and four, we get:
a+b+a-b=120+0
2a=120
a=120/2
a=60
Therefore, the value of the play chart is 60. Substituting this value in equation three we get:
60+b-(-21)=141
b=141-21-60
b=60
Therefore, the value of padding is 60.
Substituting the calculated values in the last equation, we get:
60-(-21)-2(-42)=?
60+21-(-84)=?
81+84=?
=165
Therefore, the value of the question mark is 165.