Answer:
Step-by-step explanation:
3) Number of pigs = p
Number of geese = g
p + g = 20 --------------(I)
p = 20 - g --------------(II)
4p + 2g = 64 ----------------------(III)
Substitute p = 20 - g in (III)
4*(20 - g) + 2g = 64
4*20 - 4*g + 2g = 64
80 - 4g + 2g = 64 {Combine like terms}
80 - 2g = 64 {Subtract 80 form both sides}
-2g = 64 - 80
-2g = - 16 {Divide both sides by (-2)}
g = -16/-2
g = 8
Plugin g = 8 in equation (II)
p = 20 - 8
P = 12
Number of pigs = 12
4) Let the number be x , y
x + y = 100 ---------------(I)
x = 4y --------------(II)
Substitute x = 4y in equation (I)
4y + y = 100
5y = 100
y = 100/5
y = 20
Plugin y = 20 in equation (II)
x = 4*20 = 80
x = 80
Smaller number = 20
5) Cost of soda = s
Cost of pretzel = p
2s + p = 7 --------------(I)
p = 7 - 2s -------------(II)
4s + 3p = 17 --------------(III)
Substitute p = 7 - 2s in (III)
4s + 3*(7 - 2s) = 17
4s + 3*7 - 3*2s = 17
4s + 21 - 6s = 17
21 - 2s = 17
-2s = 17 -21
-2s = -4
s = -4/-2
s = 2
Plugin s = 2 in (II)
p = 7 - 2*2
= 7 - 4
p = 3
Cost of soda = $ 2
Cost of pretzel = $ 3
