Answer:
(a;b)={(17; 64); (64; 17)}
Step-by-step explanation:
a+b=81 => b=81-a
a*b=1088
a*(81-a)=1088
-a²+81a=1088
a²-81a+1088=0
a²-64a-17a+1088=0
a(a-64)-17(a-64)=0
(a-17)(a-64)=0
=> a=17 and a=64
for a=17 => b=81-17=64
for a=64 => b=81-64=17
(a;b)={(17; 64); (64; 17)}
Divide

by 5. Or multiply it by 1/5.
You get - 56/25 or

pounds per month.
Let
x be the price for a pound of ham
y the price for a pound of cheese
<span>1.3x +0.8y = 11.28 ....(1)
1.5x +1.2y = 14.76 ....(2)
Lets multiply (1) by -1.2
Lets multiply (2) by 0.8
-1.56x -0.96y = -13.536 .....(3)
</span> 1.2x + 0.96y = 11.808 .....(4)
If we add (3) and (4)
-0.36x = -1.728 ............> x = 4.8
We substitute in (1)
1.3(4.8) +0.8y = 11.28
y = 6.3
Price per pound of ham = x = 4.8
Price per pound of cheese = y = 6.3